It's the other way around, gunpowder enabled semi-professional and eventually conscripted armies. Early gunpowder weapons were difficult to work with and sometimes relegated to professionals, but by the time guns were transitioning from arquebuses to muskets, they were standardized and simple enough to hand out to untrained soldiers and expect decent results with a little drilling.

Before the advent of guns, going back to classical times, line infantry relied much more on cohesiveness while engaged to work, which required training and experience together. There's a reason that, when mixed armies of pike and musket infantry were fielded, the pikemen were more often hired professionals - their job was more difficult. A peasant levy armed with whatever polearms could be gathered or manufactured just wasn't the same, and was likely to lose cohesiveness the moment battle was joined and rout - which is when most casualties are sustained even today.

There was also an economic aspect to levying the peasants. Imagine if Wal-Mart were to go to war with Target today. They could levy their employees to go off and fight - but they'd be losing vital manpower in their stores, which are what earn them money, and a formation of cashiers and shelf stockers who don't want to be there is unlikely to fare well on the battlefield. Instead, they could hire Blackwater Executive Outcomes XE whatever Erik Prince's private army is called nowadays, with some of that Trump tax cut cash that they were totally planning to pay employees more with. They'd get a formation of competent soldiers who like their jobs, and their employees would remain in the stores to keep earning them money. Much better, right?

Peasants were so disregarded as a military factor that the German nobility was repeatedly surprised during the Hussite Wars - enthusiastic, trained formations of mostly peasants and city-dwellers repeatedly trounced everything the German aristocrats could throw at them.