I've been playing 2NL for about a month now (~10 hours per week) and I do think it is beatable, but I am playing without a hud, so I do much better when taking notes to help me remember regs vs. fish. I've chatted with a few people that play 5NL and their contention is that if you fix your leaks at 2NL you will be a much stronger player at 5NL.
bet most people couldnt beat 2NL, especially considering high micro stakes rake
This is the stage I'm up to now. I currently have a 6bb/100 win rate at 2NL over 50k hands, the vast majority of which I played without a HUD, so I can safely say that I've beaten 2NL, but I'm getting absolutely slaughtered at 5NL (-33bb/100 win rate over 5k hands). I think I need to accept that even though I've beaten 2NL, I still have a lot of leaks that need fixing before I can hope to beat 5NL.