While I've occasionally had an engine part fail most of the major repairs I've needed to do to cars over the years has been suspension related, it's consistently abused and closest to the road / debris.
That said... many of the different EVs sit on the same base, so maybe it won't actually be as hard to get parts as it seems.
It's not just repairs, maintenance too
Oil changes, timing belts, spark plugs etc. It really helps if you have no metal touching metal
Chinese EVs are more eclectic than western EVs. But ya, suspension parts....are those things that automakers innovate on? Though I guess BYD is an exception, since they own their own parts maker.
Innovation is rare among the broad consumer car market but modify to fit new bodies and motor layouts, yes, for sure. For most mainstream cars however you'll often find that a few models per generation for any given manufacturer either share parts or are interchangeable.