Derailleur hangers come to mind, some brands use a different version in the same model lineup and model year. It's on purpose to confuse an make it difficult for the average rider to DIY.

Also Cannondale, famous for using non-standard parts (and tools) for no apparent reason.

I take it you never heard Van Moof bricked bikes afteir their bankcruptcy?

Edit: and thinking about ebike motors and their parts - bosch has locked down their engines real hard

It's red because there's nothing forcing bike manufacturers to continue down the path of repairability and outside of the enthusiast community, people might not care much, they'll just buy what's cheaper.

That is probably a reason there are no special regulations for bicycle yet. But it is still a good idea to protect it.

Did you ever repair a bike? Its like every model has its own special tools that you need to get Something unscrewed or pulled of. (You can buy them, though)

Electric Bike for enshittified