Yes, entering a market with a huge war-chest and dumping an absolute fuckton of free product is one way to attack a monopoly. There's a reason they had to do that to gain any traction.
I've paid for one game on there. It was an exclusive and is the only reason I finally installed the damn thing. I think I'm up to about 150 games on Epic, and I didn't even get in near the beginning and have missed a few since. What they've managed to buy from me, with that, is a +1 in their install-base stat because the free games every couple weeks keep me from uninstalling it, but I still buy everything on GoG or Steam. I don't even care if epic has a lower price, I use one of those.
If Stadia had taken the same approach, the average account would have spent $100 or less but would "have" $3000+ worth of games.
Why do publishers not offer end-users the right to transfer games from one service to another? That would allow new platforms to compete.
I can understand that established services like Steam oppose the transfer of licenses. But why don't the less established services remove the fear of losing access by making the licenses transferable among themselves? This must be prevented by the publishers. What's their benefit?
GoG did something a little like this. You could add copies of some games in Steam to your GoG account, by linking them—not just, like, letting you launch them through the same interface, but you'd "own" a copy on GoG, too.
I don't think it really took off. It was a little clunky and I'm not sure they got enough buy-in from publishers that the catalog available ever expanded much past their initial offering.
More broadly, I'd love to see a strict, legally-mandated separation of media distribution and production. Mostly for the film and TV industry (there's precedent—the US only very recently stopped barring movie studios from owning movie theaters, because it caused serious problems in the past, similar to how vertical integration of studios and streaming platforms is making things worse today) but maybe something similar would help the game market work better for consumers/users, too.
Decoupling the physical media from the license to access that media would be a huge boon for consumers and creators but publishers will need to be forced into it.
The ideal would be an open system where you can buy a license directly from the creator (or from a publisher on the creators behalf) then retrieve that content from any publisher by presenting your proof-of-purchase.