Nobody cares about PEP-517 or any PEP for that matter since PyPA decided they are above it. PyPA decides how things are done, PEPs are just "historical documents".

Nobody cares if package metadata is standardized. The tools aren't. The tools are the problem, not the package format.

Well, if the poster says something that is blatantly untrue, how would you call them? Liar describes exactly someone who intentionally tells something that isn't true.