There’s actually a lot of interesting recent work that points to wage labor being very prevalent in the Roman economy! The idea of slavery as the main driver of the production of the Roman economy is not nearly as popular now even amongst academics who take a ‘primitivist’ view of the Roman economy (ie that it resembled the customary economies around it more than later, early modern economies). Though, obviously, either way it had significant social influence and implications, and was far from economically inconsequential.