Ehm just to clear up a few things.
Samsora is a super good player, and easily one of the best Peach players in the world as he has proved in this tournament. However, he wasn't ready for the MK matchup. Knowledge of the MK matchup is very specific as it requires a lot of edge camping, until you're out of 0-death percent. Samsora actually did do this at the beginning of game 1 where he kept running to the ledge. It worked out and he got a 1 stock lead, but he stopped doing it from the second stock onwards for some reason, and got punished hard for it. I wish he had continued his ledge camping throughout the set, but oh well.
I am not experienced vs Meta Knight myself, but my source for this is Umeki, who has plenty of experience vs Meta Knight, most notably vs Abadango's Meta Knight himself. He told me that as long as you ledge camp, the matchup is actually super doable, because after 0 death percent Peach actually does pretty well vs him. Even in Samsora vs Abadango you could see that if he managed to survive past 35, the tides would quickly turn into Peach's favor. Peach likely still loses the matchup, but it isn't even nearly as bad as we saw yesterday.
(As for Rosalina vs Meta Knight, Kirihara has beaten Abadango's Meta Knight after the patch, with pretty much the same tactic.)
It's quite funny how it's stated that Peach is a bad character the day after she gets second in a tournament being used for 90%, beating one of the best players in the world and a Diddy Kong who is said to be one of her oh so hard match-ups. Peach is also said to have "no results", yet in
@Das Koopa 's results thread, she is top 20 easily. The results are certainly not suggesting "Peach is a bad character", unless you consider upper half in the cast as bad.