there are number of "dutch bike companies" that sell bikes with stainless steel rims. I thought those were bad/old. Why would you do that, do they last longer?

Cheap.

I hate steel rims. They are heavy, no braking at all when wet,
did I mention that they weigh a ton?

Never heard of *stainless* steel, but I know chrome-plated rims mean no-brakes-in-the-rain.
Since stainless steel is even tougher than regular steel, it *should* mean a thinner wall thickness could be used to reduce weight.

Stainless steel is actually a good bit weaker in most regards than a nice alloy steel. I'm not exactly sure what properties make for a good rim, but as a rule of thumb, nice alloy steels work better than stainless.

I have ss rims on my 1960 Gazelle 3 speed Dutch built. Bike probably weighs over 50 lbs.

The only advantage stainless steel rims have over other steel rims is that they won't rust. Steel rims in general have fallen out of favor because of their weight and poor braking performance in wet weather.

Caliper brakes on steel rims are poor in dry conditions and dreadful in the wet. However, if these bikes have drum, disc or coaster brakes the rim material is a non-issue.

"Stainless steel" can be weaker or stronger than mild steel and even Cr-Mo depending on the alloy used and the heat treatment. The term stainless steel covers a huge range of compositions and properties.

Chrome steel is extra slippery because the base plating metal which I think is nickel builds up in the low parts of the roughness and soon results in a mirror smooth finish.

Stainless might be a far different story.

Wheel rim alloys are probably chosen for their cold forming properties rather than maximum strength.

If you are rolling around Amsterdam at 6 MPH, neither weight nor braking matter very much.

Braking matters -- it's either that or run down foreigners walking in the bike path. Nothing gets you shouted at quicker than walking in the bike path...

Coaster brakes or drum brakes make the rim fine, particularly since Amsterdam'ers
when the city was growing, and they were Importing Warehouses,

were taxed by buildings frontal width, so they built narrow but high,
they the daily transport bikes, don't get brought in ,
they stay locked up, outside, in all weather.

The race bikes they ride on the weekends do.. come in and up the stairs..

My Dutch Raleigh Cameo has stainless rims with the little diamond patterns embossed into the sides. These shiny rims look beautiful but the braking is awful with the rims. All the pattern on the sides does is make a little noise when the brakes are applied.

If I could find 700C SS rims I'd switch my drum brake bike to them. Rumor has it Araya made some but I've never been able to find them.