That's not really the case though. I was well aware that it doesn't work on older devices, it's not supposed to. There's nothing to test/fix because it simply doesn't run. ...
Sure, it does not run, but can be accessed. And as such there is the
possibility that the "wrong" people will do so. That's something which needs
to be addressed ahead of time/release, if you ask me.
... The problem is poor signaling from Apple's side on the App Store (and the fact that users don't read the very first line of the app description somehow). ...
No question about it. But did you know about the 'bad signaling' before
releasing the game?
... A good comparison would be people buying a DX12 only game on Steam and complaining that it doesn't work on their Windows XP machine.
Indeed. But if I know this ahead of time I can take counter measure. If the
vast majority use the proper DX12 version and only a few try to run it on XP,
who cares? But, given your example, if I'm going to go with DX12 yet the vast
majority is on XP while my game will be released on the same market for those
XP people to try, then it appears pretty obvious to me that I'm up for a
shitstorm to arrive, no? So, if there isn't any fallback, like Popstar said, I
have to think about whether I should go with the new lib or not. And you have
decided to go with Metal-only for some very good reasons of yours. But given
that your game's success may struggle given all these 1 stars "... I'm
getting lots of people buying it and then leaving nasty 1 star reviews because
the app doesn't run. ...", then the decision to go Metal-only was either wrong
or the benefit of going Metal-only outweigh all these 1 star reviews. Tell me.
Don't get me wrong. I know it sucks getting rated that way for an issue which
isn't yours (technically) and which could be addressed easily by Apple (as
Popstar has indicated). But what's important for me is knowing whether the
problem was known ahead of time (or not) and how the decisions were made to
use one system resp. library over the other facing all the consequences.