I'm not sure that's true honestly. They are a notch below Barcelona, yeah, but that's largely because of Messi. Xavi was amazing and probably the second best player he's ever coached, but I'm not sure how that version of Barcelona would do in 2024, facing opponents that evolved to beat them. They were struggling against Mou's Madrid by the end, and that team had nothing on the Madrid sides to come, Heynckes/Guardiola/Flick Bayern, Klopp's Liverpool, or indeed City
I mean the closest comp they faced to a team like Guardiola's City would be Bayern in '13 - and yeah, Xavi had aged, Messi was injured, Tito had cancer. They were far from their best. Still, they got fecking atomized. They didn't look like they could possibly cope with that level of size, pace, strenght and organization