I was replaying Sekiro recently after not playing it since release, thought I could at least put up a fight against tutorial Genichiro. Needless to say, I got my ass handed to me in under a minute.
Just proves the point tho. I p easily win my fights against Tutorial Genichiro now, because once you know the combat system, he's a really easy boss. He just seems like an impossible monster the first time you fight him because the combat system takes a little while to click and become second nature.
My big issue with AC6 is that the method they EXPECT you to win with is not explained. Stability damage is not explained until AFTER you beat the "tutorial" mission, which is just bad design, and expects you to have played a FromSoft game with that system in it. If you're like me who's coming in from Verdict Day WITHOUT having played a Souls game, it's just a rough fight.