[ethan_g]

The thing about this approach--where you learn by assimilation rather than structured study--is that it you need to have amazing intuition for it to work. One of the benefits of structured study is gradually building intuition of the definitions and theorems. For someone of Scholze's caliber, the intuition is already there before any study. Structured study of linear algebra probably wouldn't have done much for him other than assigns names to theorems and definitions that he already intuitively understands.

I might make an analogy to studying music: for the majority of people, it takes a lot of structured study to develop a good ear (i.e. being able to write down melodies and harmony after hearing it). For example, you'll study intervals, chords, and inversions, and extensive practice identifying them on hearing--just as you learn theorems and definitions in math class and do problem sets to practice applying them. But some people innately have a very good ear (e.g. perfect pitch) and don't need a course to teach them to identify intervals and chords. Even though they might not yet know the names of chords and intervals, they already "understand" them.