Zuckerberg had big push in 2015s to reenter PRC, Google had Dragonfly, but IIRC they were killed internally because employees protested at least for Google. Bing's still in China. PRC fine with western platforms, as long as they censor like domestic PRC platforms and hand over dissident info, where dissident is whoever PRC says it is. Morally it's complicateded, economically it's probably not that profitable in long run, but regulatorily, it's straight forward. If anything PRC would love to have that leverage and try to get western platforms to extend censorship to PRC dissidents abroad.