If I never used it, I would come to the same conclusion as well. But there are people who advocated this gameplay to no end.
Also, magicfind on D2 merc only works if merc is capable of killing stuff, despite magic find trash you loaded up onto him and survive. In case your merc/hireling can’t kill anything, it’s a waste to let him attack on its own as it would be more beneficial for you to kill things much faster.
Magic find weapons you keep at your alternate slot will not allow you to buff yourself or debuff enemies reliably in combat to speak. Which is much more viable than carrying a magic find item with no utility. Fortunately you have a vast inventory space to carry magic find gear and swap them in a whim while debuff or buff still lasts on duration.
Charms only halted it down so you can only have around 50-100% mf whenever you want, sure, but not 200-500% or more in a whim, that’s the drawback. It draws the line between magic find characters and damage output. You can’t have high damage output and utility while also stacking magicfind%. That’s the issue they addressed by locking your inventory space for power layer, while allowed some powercreep.
You can assume anything, doesn’t make it truth or right. Guy worked in a team of 20 with 3 head names.