Most celebs are conservative in reallity, just like most rich people, no one wants the gobernment in their wallets.
A lot of athletes, ex-athletes/performers etc., are VERY conservative. Not even just fiscally conservative but socially too.
WWE/WWF dudes in particular are probably a lot more conservative or libertarian than we'd realize.
Rock strikes me as a moderate that probably likes the George Bush Sr. type Republicans but not the Trump Republicans. He voted Biden since Biden is basically like an old school Republican or Democrat...when the two were much closer to the center. He definitely ain't on the Bernie, AOC, Ayanna wave but he doesn't want to piss people off.
Since he wants to be in Hollywood, he can't go too far bashing the left. He also wants the WWE fan support so he can't get at the right either.