Weren't we saying passing was way down last year too and it trended waaay up the last 8ish games? I feel like this came up in discussions last year too, where some QBs (Burrows comes to mind) exploded from week 10 onward. Burrows was like 250/game until week 10 and then 330/game the rest of the way. I feel like someone pointed out a few other players with similar stats (Josh Allen and Mahomes both follow the trend it seems)
I think offenses get more film on what defenses are doing and start to exploit them.