When is the last time you have opened itch.io and bought a couple of games?

The reason this isnt happening that much anymore is that the standards for games have increased for the average consumer, so development costs have increased to fit those standards. And even then, publishing your game in a monetizable way is hard and often requires starting capital now.

And when it is happening, it is happening on roblox. When is the last time you have opened roblox? It is more or less exactly what you want -- teenagers make either simple games or free copies of more popular games and then fill them with microtransactions to make money.