Valve makes it very very easy to be a PC gamer, and, importantly, slightly harder to be a PC gamer who buys games in places other than Steam.
Yes you can buy games on GoG or Epic and play them on a steam deck or a steam machine. But it's juuuuust enough faff to be annoying enough, that you'd rather just get them on steam. I know people (and am a person) who have rebought games they already own so they are on steam, to make playing between steam deck and desktop more reliable.
It's the same with the steam controller. You _can_ use it with games outside of steam, but it's enough of a faff that you find yourself avoiding it.
It's incredibly effective, and why they are an effective monopoly in PC gaming.
Yes you can buy games on GoG or Epic and play them on a steam deck or a steam machine. But it's juuuuust enough faff to be annoying enough, that you'd rather just get them on steam. I know people (and am a person) who have rebought games they already own so they are on steam, to make playing between steam deck and desktop more reliable.
It's the same with the steam controller. You _can_ use it with games outside of steam, but it's enough of a faff that you find yourself avoiding it.
It's incredibly effective, and why they are an effective monopoly in PC gaming.