Wouldn't it be fun if electric cars were the same way as PC's. Plug and play the parts you want, switch motor / battery.. choose a new chassis as you wish. And LED lights of course.
And really, the subset of the market that still follows these standards is small, and shrinking. The vast majority of PCs today are laptops with few, if any, swappable parts.
Pretty much the only segment where this still exists is the enthusiast subset of the gaming PC market.
It is a bit more complex than that of course and generally speaking you are right.
Things like ATX power supplies, ATX/mATX motherboards, tower cases, are pretty squarely for the PC gaming segment now. It's difficult to even find a "business" motherboard these days, where as 20 years ago, they were nearly all designed with this use-case first. There's ASRock Rack type stuff that targets some custom server-type use cases, but the big server manufacturers make their own proprietary stuff.
there are options out there for itx and matx server chassis, even ATX and EATX.
Silverstone in particular has some interesting options for rack mount workstations based around 360mm AIO water-cooling, ATX boards and PSUs, consumer GPUs, etc. though those are meant more for the half and quarter rack enclosures designed to be installed in a home or office environment.
But most of the market is Dell/Lenovo/HP/Supermicro (and in China, a couple other players).
Silverstone is an absolutely tiny business by comparison. Their US office is 1/6th of a shared warehouse space in an LA suburb, next to a laminate flooring retailer.
https://www.tiktok.com/@hu_changwen/video/736154455749586460...
That’s no longer true for the most consumer laptops.
This stability thing is just a weak excuse used by car companies.