I think this is entirely plausible. Grothendieck did not walk the established paths, but invented lot's of new concepts as he was working on problems. IIRC he was largely an auto-didact in his early years. In his work he never tried to reconcile the existing theory, and somehow improve it. He started form a blank slate (see EGA/SGA/FGA series of books) and build-up the proper concepts (Schemes,K-theory,Categories) that would allow the problem to unfold in the most natural setting and slowly resolve itself: https://ncatlab.org/nlab/show/The+Rising+Sea

Sometimes ignorance is a blessing. It frees you from keeping all the historic clutter in your memory, and see an un-distorted picture.

Grothendieck worked in algebra, this is analysis.

He started his career as a functional analyst, actually, but yes he was an algebraist by inclination.