ZD, I think you’ve got it a little mixed up.
The issue isn’t whether an irreligious Jew can sell his chometz, it’s whether the sale is considered a sham if he keeps his business open on Pesach.
R’ Moshe was actually mattir (although the beer bought by the company on Pesach would still be a problem), but the Star K, OU, and others follow the opinion that it’s not a valid sale.