However, I don’t think you that means you should skip watching 3B1B videos at all. In fact, Grant repeats quite often in his videos that they’re not a substitute for doing problems.
I’d highly recommend watching the videos side by side with reading through Axler. They will help develop the right geometric intuition (which Axler does a decent job of, but books can only do so much as a medium). I believe the 3B1B videos can also be quite motivating, which in my experience is the most important factor when self studying.
I'd say the same is true for proofs. Simply reading a proof isn't the best if you want to understand/retain it. If you can "re-invent" the proof step by step (or in some contexts you might be able to translate steps between geometric and algebraic representations), then you have probably internalized it sufficiently.
I was wondering how you feel about Professor Leonard? He's pushing recordings of his college classes online on YouTube. It's a veritable trove of useful lectures. [1]
I would advise following a more traditional path, with a good book, but I cannot think of any good reason to not take a break from the book to watch some related 3B1b video from time to time.
I'm a firm believer that you don't truly understand material unless you also understand a proof for it. Ane while those resources are AMAZING for simple intuition building, they aren't sufficient.
Go pick up a book about proofs to develop mathematical maturity and then delve into some undergrad books for analysis (Abbott) or linear algera (Axler)