A few takeaways from the Valve monopoly lawsuit:
The only viable way to sell your PC game is through Steam. (EA tried for 8 years to do its own thing and had to give up.) But to do that you must let Steam basically price fix your product, which destroys any potential competition.

And if you're lucky and get some Steam Keys (which is a revocable privilege), it's forbidden to sell your product for a lower price on another store. Publishers are afraid to death of being removed from Steam, which would destroy them, so they can't rock the boat or risk ruin.

Steam's forced monopolist price fixing (which is required when you sign the contract with them) increases the prices of PC video games, hurting gamers. The up to 30% cut hurts developers, especially smaller ones and indies.

In addition, Valve employees have access to all sales and usage data for all of its competitor products, including competitor app stores (from the sales of Steam Keys). It can continuously fine tune its monopoly, preventing competition or price discovery.

Everyone involved (the customers, developers, publishers, even competing stores) is being used to continue the Steam monopoly.

According to the lawsuit, "Valve has threatened publishers".