The design's been the same for as long as I can remember. Unscrew the dustcap and you get a little knurled nut which also needs unscrewing before you can pump the tyre up. and after pumping, you screw it back up again.
And, if you're a bit hamfisted like me, the central screw thread gets bent. Still works, mind. No big deal.
Then it snaps off, and you need a new tube.
I never got round to getting one. 5 years ago this happened; I have to depress what remains of the central screw in order to enable air ingress. The air pressure forms a seal which isn't easily broken.

One might reasonably ask if the design ought to be simplified after all this time . . . .

I've been and broken them, too. These days I just unscrew the core a wee bit to prevent bends from the pump head. I have ham-fits, too. 😁

I would be leary of what the "improvement" would be like.

The problem isn't the design.

I'm not trying to insult anyone but "I'm ham fisted" is just an excuse. Decide to be gentle and stop breaking your gear is the solution and the fact is that millions of people use Presta valves without issues.

FWIW, some tubes come with replaceable valve cores. They can be replaced and you will need to know how to do this if you ever go to tubless. -Tim-

Titanium valves?

Mechanically, presta valves are good. Intuitively, the design is bad because it does not account for the human factor. The evidence is the learning curve and how many users break those valves. This can be disastrous when trying to pump up a tire in the middle of a ride somewhere and you end up breaking the valve and doing the same thing with your spare.

An example of bad human factors design is the smart phone. One phone requires you to swipe the central spot to the right to accept and to the left to decline the call. Another phone requires you to swipe the accept button past the big circle to accept or to swipe the reject button past the big circle to reject. Many times I had intuitively just tapped the buttons but to no response. On a land line, all you need is to pick up the phone.

Other examples include the kitchen stove and aircraft landing gear levers, etc.

Pssst!
It is presta, not presto.

Prestas are for bikes, just as Schraders are for cars. My floor pumps work with both.

Throw away the 'dustcap' when you first install the tube and the process is a bit simpler - the only function of it that I've found is to keep the sharp end from puncturing the tube as it get jostled in your bike bag. There's no way for any dust to get inside the valve once it's screwed closed.

Then either stop being 'ham fisted' or switch to Schrader valves (harder if you have deep rims that require extra long valve stems).

The other function of a dust cap is to keep the valve end clean. If you ride in wet grit or mud, your valve will get dirty. Then when you go to pump, you pump a little grit into the valve. This grit can keep the valve from seating properly and then you get a slow leak you can't find or a damaged valve. I've had this happen. The no-cap thing started with racer types who don't like the weight of it (!), or the time it takes to put it off and on if they're trying to get a quick pump-up for a slow leak. It doesn't weigh anything and in the long run, it protects your valve. However in the short term, you get derision from the same people who never wear mirrors because they're faster than anyone and don't have to care about who's behind them.

You're absolutely correct about having caps on the tubes in your bag. I've had an uncapped tube cause an abrasion puncture in an adjacent tube. However if you don't replace the cap on the tube after installation, you'll lose it and then what are you going to put on the tube after it punctures, you patch it and then put it back in your carry bag?

Mr. Practical here who rides well enough that I don't have to care about what anyone else thinks about my choices.

they already improved it when they invented the Schrader valve

I'm either pumping up a tire after getting a flat in which case it's the replacement tube (with cap) which is clean or I'm pumping up at home before a ride in which case it's easy to clean a muddy valve stem. Could be an issue with mountain bikers who adjust tire pressure along the way depending on surface conditions - but not for road riding. The weight of the cap is not an issue, but it does take an extra step to remove, keep track of it, and replace.
I do the patching and putting back in the bike bag at home where I have an assortment of the little valve caps.

King Kong tested, King Kong approved.

Right. It's only Presto if you can produce a tube out of thin air...

they make them w long valve stems. happy to share w any other hammys out there

I'm not ham fisted and I find them finicky. And annoying. I carry a shrader adapter and use it. Haven't had a valve issue since I started doing that. Works better with both my floor pump and hand pump since it covers the fragile part of the Presta securely.

There have been times when I dearly wished I could...

Yeah, I read this figuring they'd come up with a new magic valve. Alakazam! Your tire's filled!

Wait, what? You've been using the same tube for 5 years?

Don't wiggle the pump head side to side when putting on the pump or taking it off. then you don't bend the presta valve threaded rod.

I rescind the POTD award I gave earlier in the day and give it to you.

Thank you for all those brilliant suggestions, guys . . . .Now, i always understood presta valves were for high pressure racing bike type application, and Schraeder were for motors, and mountain bikes.
I know of many racing aficionados who simply over pressurised their tyres to save a millisecond or so. But they blew either their tyres or their valves thereby not only failing to win, but also to finish .. . . I don't use a tyre pressure gauge; rather -
when the pumping gets tough . . .
I've had enough.
And your max pressure for a presta is . . . .drum roll . . . .

I get very annoyed by the threaded presta valve bodies. I have to yank hard to get the pump head off the valve. Grrr.

The Michelin Airstop tubes are very nice. No outside threading, so there's no spin-on nut, and the pump head removes with no drama.

There's no advantage to extreme high pressure (well, maybe on newly paved roads or velodrome tracks.)

It sounds like you are using a small carry pump, instead of a floor pump, which always have a gauge. Yeah, pumping until it's quite difficult works okay on those tiny pumps.

Floor pumps are way easier and much faster. And you are less likely to bend the valve nut, or rip the valve out of the tube. And you can see the pressure you are putting in.

At 170 pounds, I use:
With 25mm tires: 95 to 100 psi rear, and 80 to 85 psi front. It's comfortable on rough roads, and still very fast rolling.
With 29mm tires: 80 to 85 psi rear, and 65 to 70 psi front.
I don't use 23mm tires any more, but I think I had 105-110 psi rear, 95-100 psi front.

AFAIK, there is no difference in max pressure between Presta and Schrader. Presta is preferred in high pressure tires because high pressure tires go on narrow rims, for which the wider bore of a Schrader valve causes structural weaknesses.

I've never heard of a racer blowing a valve owing to overpressure, and stories of others' lack of judgement don't really figure in my choice of bike valve.

I'm not really understanding how the core screw gets bent and doesn't have enough thread remaining..? The pump valve head slips on & off over it. Why would it bend and break off?