Same was said in 2020 with Van Aert winning Strade, San Remo and two stages in the TDF. Then Van der Poel won Flanders late 2020 and Strade 2021. First week of the TDF was all about MvdP, but he quit and again WvA took over.I am one of the biggest vdP fans out there,, at least probably in the USA (Senna maybe on par)...and I have to admit I am a bit jealous of how WvA has surpassed MvdP at this moment. I don't know if he has a better training program, better team, better makeup, or what, but it's interesting to see this split in their careers right now. We can say, oh but wait until this or that, but at the moment, 7/2022, this is how their careers have developed.
Having said that, based on what I've seen so far, they DO go through these periods of one clearly being stronger than the other, but for certain it's tilted in WvA's side right now.
A lot has to do with physical issues by both. And the fact that they are different riders. WvA seems to be better at GT's, both by racing style as due to his strengths (TT, sprinting, climbing). While MvdP seems to be better at classics for the moment. Also don't forget he's been focussing on MTB as well