This is great for smaller devs as you basically have 0 advertising budget and rely on worth of mouth for your game to be a success or not. So you can take guaranteed money and pay yourself (and your employees) or take the gamble and hope your game sells well.
Also Epic takes smaller cut then Valve does on Steam. (12% vs 30%)
Also these exclusives to Epic are timed. So after a couple months the developer is free to publish their game on Steam/GOG/Windows Store/whatever PC platform (Epic store exclusivity does not apply for consoles)
But I was also thinking in terms of actual platforms like "Xbox only for N months"
Digital collections certainly have privacy tradeoffs. Though I'm quite happy with many of the upsides: cross-play, automatic cloud save, (sometimes) cross-save, no disc swapping, fewer things to clutter my living space.
I still don't get how the exclusives are a good deal for the creators. They get more publicity and probably some extra money for the contract. But does it really offset the lost sales? There was a large number of times when I went though: this game looks awesome, I'll buy it, oh it's exclusive for whatever-platform-i-don't-have, ... and likely not remember about it ever again. I even bought similar games which are available on platforms I already have instead.