Meh. I don't think Law & Economics has ever become nearly as influential as Scalia's Original Meaning did. Not long ago everybody seemed to admit Scalia's constitutional philosophy had become the new orthodoxy that even liberals (with some distaste) came to embrace. But since his death Scalia's ideas have been so thoroughly and rapidly corrupted (Embrace, Extend, Extinguish?), particularly by conservatives, that I'd argue their influence is barely recognizable today, mostly as a peculiar phase or detour. What remains are his incoherent addendums (i.e. amateur historical exegesis) he tried to develop to make it work when it became popular. Law & Economics will probably remain influential for a much longer time, but only because it'll remain a minority approach or one approach among many in a toolbox.

If Posner had been elevated to the Supreme Court so a cult could develop then the same thing might have happened, though I think Posner was less doctrinaire so maybe the trajectory would've remained the same.