You also seem to be thinking of Candy Crush style games, whereas I was pointing out that in recent years some of the most popular mobile games are FPS, RTS, also things like Honkai: Star Rail and Genshin Impact and other action games. On the other end, desktop games have also become monetization machines in the same fashion - Fortnite, Apex, CS:GO, OW, Minecraft, Roblox are massive money-making machines. Any judgement about mobile games being 'less fun' or 'less serious' is entirely subjective.

This thread started because someone though Steam stands as the universal entrypoint to gaming in general, which is absolutely far from the truth.