The core issue in the original Fighter of the Old School was a Christmas Tree.
Fighters, like most PC classs, capped onlinear power after some point. They didn't get to the 5e equal of Tier 3. Instead the magic item tables were tilted hard to them. So your level 15 had level 10 features but a magic armor, a magic shield, a magic belt, a magic cloak,a magic helm, magic boots, several rings, magic potions, a golfbag of magic weapon
that they could only use and got everytime.
However D&D started to nudge to letting DMs control treasure to make low magic, no magic, or low fantasy settings. And fighter players wrote wishlists as these items were their class features. And when they didn't get them, the fighter players wanted the item aspects as class features.
That's the conflict.
- You can't have the fighter's class features be items AND not have class favoritism
- Only one of the DM, the Player, and the System can choose fighter items.
- The System has to choose whether the fighter is a normal world person boosted by items or an exceptional person where items is a bonus on top or factored it.
The D&D community has be dodging the issues for 50 years.
AKA
Either the Fighter gets to pick the Gauntlets of Ogre Power, Belt of Giant's Strength, and Hammer of Thunderbolts everytime, the Fighter gets Thor's power and skill asbase features, or the Caster lose the ability to pick spells a level up.