As an aside (and not a comment directed at anyone in particular) I just had a chuckle. For decades I’ve seen arguments how fighters got screwed in AD&D because they are so dependent on magic items while MUs can cast reality bending magic, and now when I see folks point out how MUs often got screwed, the reply is “no they aren’t if they get all these magic items!”
Maybe 1e was more balanced than people give it credit....
Umm, I think you're getting your 3e discussions mixed in there. No one ever claimed, AFAIK, that fighters in AD&D were dependent on magic. FIghters had the best survivability, and frequently (particularly if you used Unearthed Arcana) dealt the most damage. It was 3e that screwed over fighters so badly and made the casters king.
And, that's also putting words in other people's mouths. The point that was being made is EVERY character in AD&D would have 10+ magic items in fairly short order - certainly by about level 7 or 8 anyway. You cannot really discuss the fragility of MU's and ignore that fact. The modules certainly rewarded groups with those kinds of numbers of magic items. So, claims that "Oh, well, in my games, no one ever saw anything above +2" is just arguing from anecdote. Cool for you, I guess? Our groups, which tended to abide by die rolls, and heavily used modules, saw far, far more magic than that and far more powerful magic than that, fairly often.