Right but there definitely are things that were different in the past but are never really going to change in the future (because they are de facto standards).
A byte is now always 8 bits. Integers are always 2s complement with wrapping arithmetic. Nobody is going to make a CPU that doesn't use those (at least nobody that wants people to actually use it) because no software would work on it.
For example RISC-V set the cache line size to 64 bytes because that's what everyone else does and going against the grain is too difficult now (and maybe there was no reason to in that case but still...)
The only thing I can think of that benefits from C's "nothing is well defined" approach is CHERI, but I bet a ton of code needs fixes to work with it.
A byte is now always 8 bits. Integers are always 2s complement with wrapping arithmetic. Nobody is going to make a CPU that doesn't use those (at least nobody that wants people to actually use it) because no software would work on it.
For example RISC-V set the cache line size to 64 bytes because that's what everyone else does and going against the grain is too difficult now (and maybe there was no reason to in that case but still...)
The only thing I can think of that benefits from C's "nothing is well defined" approach is CHERI, but I bet a ton of code needs fixes to work with it.