This guy gets the idea.
Basically they are still very close to the English designs they were based in the early 1900's. Since then typical Dutch has been the cloth full chaincase, focus on rust proofing and low mechanical drag, high and wide handlebars for comfort of a very upright riding position, better vision and restricting the exercise to the legs, and extra tubing as in cross frames and double top tubes. Geometry keeps them in a straight line easily. Fenders, lights, bottle dynamo and reflector, bell, a rear rack that holds a passenger and an O-lock have been standard for ages. The luxury models typically had a Sturmey Archer IGH allthough there have been Dutch designs and drum brakes, rod or cable operated. Yes, it rains quite a bit here.
Recently Dutch bikes have become less durable, with the exception of Azor (/Workcycles) from the video, that's a relatively young manufacturer that wanted to offer old fashioned reliability and durability again. Front racks are now often standard, there's wider aluminum tubing and fat tyres, more often IGH's (shimano) and no more rod brakes. Lights are battery or hub dynamo and the O-locks have a insert cable. Other innovations are the front rack that doesn't turn with the wheel, a stop to prevent the frontwheel swinging, double kickstands, child seat mounts and gear shifter protectors. Don't think anything other than the bottle dynamo is taken off, but chainguards are more often used instead of full chaincases. I wonder if that will stay now the skinny jeans fashion is ending.
The archetypical Dutch bike is a black single speed coaster brake step through with a crescent upper tube that used to belong to someone's grandma in the fifties or even thirties. Hence the name 'oma' which means grandmother. It's an English design from 1904 if I remember correctly, but they got popular among the kids in the 80's again when their grandmaothers died and they turned out be very well made, made girls look elegant and boys look cool. There's something with the geometry that makes them one size fits all. There are 12 year old girls riding them who are 5 inches short of touching the ground when seated, and guys over 7foot. There's company who leases bikes, for about 15 euro's a month you get one and if there something with it like a flat tyre, they come and swap the bike for a fresh one. These are allmost all this model, but they don't feature a rear rack, most likely because taking a passenger would wear them out faster (allthoug people sit on the front racks). They have a blue front tyre and all kinds of colours otherwise the customers wouldn't recognize their bike from the other swap bikes.
So in a 100 years we've gone from this:
To this:
