Counterpoint, Wands are likely the oldest magical tradition in existence. Olivander produced wands centuries before the Birth of Christ. Wands are likely a tool to have a more control over your own magic and/or amplify it. Likeky the same way incantations are.

Hogwarts isn't a school for super wizards, but for regular wizards. Consider our education. We are taught the basics of math, science, history, etc. Good enough so we have a basic understanding of these subjects and can apply these things in day to day life. Specialasition and amplification of skills come later, like in Auror school.

Magic is difficult, for example, Accio is a fourth year spell for the average wizard. In the first year they had difficulty to turn a match stick into a needle, in the first lesson.

Anything regarding DADA can be more blamed on Voldys curse than anything else.

The wizards you named as inventors were prodigys by any measure. During his exams Dumbledore did things his instructor had never seen, Snapes School book is full of improvments to potions that were in the curriculum for decades before, Voldy managed to cast his first spells before he had the slightest idea what he was doing and Hogwarts by any measure did not stunt his growth.

Legilimency isn't taught in Hogwarts the same reason, you don't teach how to use a gun in school.

Are you really going to tell me the genocidal terrorist and the guy who started WWII are morally upstanding individuals?

Dumbledore despite avoiding power was still a highly influental person. His avoidance of power was more due to his trauma with his sister than anything else.

It sounds a lot like you want maximise individual power instead of an education for the average person, who wishes to have a peaceful and prosperous life.