I've been mulling over this some, me, being me, would inititally have prefered to remove them, but, on second thoughts decided , at least for my set, they serve two purposes.
A: They remove the broken files from peoples sets
B: In terms of TZX, it will help to resolve an issue over certain changes that were made to SOME, so they would only work on one, redundant, emulator.
That being said, how would you guys feel about those files being moved to ZZZ-UNK...etc etc? retaining the name where possible, obviously.
Cant help thinking , moving them to the trash..area, would stop them messing up the set in general, where at least they can still server the two functions I have listed above.
Not to mention the fact that a broken file is..essentially...unknowable