Nah Mace coming back throws nothing off post RTOS, it actually would explain how he was able to communicate with Rey...
Mace never learned that ability before he fell out that window, Qui-Gon figured it out and used it to communicate with Yoda...Yoda then taught OBi...
Mace absense in eps 4-6 can be easily explained, he was defeated, the Jedi were destroyed and he chose to live off the rest of his life in isolation like Thanos in the beginning of Avengers End Game...
Plus we'd get Boba Vs Mace..they have beef cuz Mace killed Jango...
I actually could see Mace takeing that L hard, basically living out his life on some distant planet, on some "I fukked up" ish, while the OT ish happened.