Learning to get best out of wherever you are is what works.
Regret and other feeling are supposed to come, they prove you are a human, but you have to control them and pick up the best for you by contributing your best and always being on your toes to get things done.
The overarching theme of that thread reflects Max Woolf's comments: Companies(FANGMA)place a lot of importance on Accreditation and that is pushing a lot of capable folks out of ML/AI applied roles(not talking about inventing the next capsule network that requires a P.hD).