> Valve does not.

Except they do. They control the Steam distribution network. It may not be physical but you still have to use it to reach a large portion of PC Gamers due to network effects and no one wanting to run multiple clients.

Currently you have to also make use of their other services like the Store, and pay for them with a large sales cut, in order to use the distribution network, no matter if you want those services or not.

I think you’re confusing

1. Being a monopoly

2. Abusing monopoly status.

Steam does control the vast share of desktop gaming. But has no influence on console (Xbox, playstation, switch) or mobile (android, ios). They are a monopoly.

But they don’t abuse their monopoly so they haven’t broken any laws.