No real standardization in bicycles just a new standard each time to solve the problems of the old standard. However Bosch which is heavily involved in more things than you could shake a stick at but particularly automotive sectors builds quality batteries and other parts to last a long time and then will support it 11+ years on even after they have discontinued an item. The only Bosch product that you cannot get support for in the U.S. because they didn't sell them in the U.S. is the gen1 stuff which you rarely see here anyway. I can still get loads of support and parts for gen2, gen3 and of course gen4 non-smart system.

Bosch is the way to go on the front, slightly more cost upfront but very minimal operating cost down the road especially depending on the other parts involved and really truly excellent support all over the country (and world) without much fuss. For a shop that knows what they are doing it can sometimes be frustrating if not sent up to level 2 right away but they go through everything and really do a good job to make sure they figure out the problem and well document it so they can eliminate it for the future and get ahead of it right now.

I have been selling Bosch since 2015 and still have people on bikes they bought from me or my shop from that era and have even seen some older ones. Really reliable, really good quality but the support is the key. Generally when they do have an issue it is an oddball one that is less common and those are pretty few and far between. Plus add to that a lot of manufactures use Bosch and because Bosch is a very complete eco-system you won't have problems with stuff not working or going together right plus they have great software and lots of options for displays and motors and so many different kinds of bikes from full suspension cargo bikes to fun upright Dutch bikes to even road bikes.