I don't think the exclusives are good for users, but from a developer perspective this is an oversimplification. Epic is essentially pre-funding games.
If you're an indie dev who's been working on a game for 3-5 years, literally everything you have is riding on that release going well. It's incredibly stressful.
So suddenly this billionaire shows up and says, "no content changes, no interference, we'll just guarantee up front that your game is profitable. We'll just give you the money to justify the last 5 years of your life, and after 6-12 months you can sell wherever." Of course developers take that. Suddenly you have the freedom to be experimental, to make games that are personal and niche without worrying about going broke.
There's a real sense in which PC exclusives are bad for the industry overall, I don't like the direction the market is headed. But from a developer perspective Epic has been pretty objectively good for indie games. The lost revenue from not being on Steam means nothing if Epic is willing to fund your game upfront. Think about how much peace of mind that means as a developer, to not have everything riding on a single launch, to not have to spend months leading up to launch getting sick worrying about what's going to happen.
And also let's be real, from a user perspective we had Steam exclusives, even if Valve didn't directly require them. I buy my games exclusively DRM free, I won't use Steam or Epic. The number of games that refuse to release outside of Steam, or who tie their multiplayer and modding communities to Steam's servers have been a pain in my side for over a decade. There are games on GoG that are missing patches and that will never get multiplayer, because Steam just happened to release frameworks encouraging devs to make themselves utterly dependent on Valve's infrastructure.
I won't install the Epic game store on my computer. But at least a game that's exclusive to Epic games store eventually becomes non-exclusive -- on average, I'll end up getting access to it later. Most of the games that get released exclusively on Steam never get ported off and I never get access to them. It's a little bit irritating to hear people pine for the day when most devs were still effectively releasing store exclusives, just without any extra compensation and to a storefront that more people happened to use.