So why do people dislike EGS?
You launch a game, you buy it even cheaper and you get free games on top of that. This is an insane discount and I own the games. And the developers even get a better cut. So why do so many people have a problem with that?
Its incredibly feature poor and less reliable/stable than Steam, which has become the market standard.
That alone doesn't get a storefront the ire EGS has received, but Sweeney specifically marketed it as basically the anti-Steam and has pursued content exclusives specifically targeting Steam. For example, Metro Exodus was a big early get - was still available on Game Pass PC basically at launch.
In short EGS' entire hook is to entice publishers onto the store and assumes consumers will follow due to the fetish nature of video games where players "need" their favorite IPs. Its a very cynical approach and that cynicism directly informs why they do the least possible on customer features.
EGS is basically a microcosm of the the gaming industry writ large with less artificial veneers - Epic sees their publishing partners as their real customers while the people buying games there are just a commodity brought in by their customers. Thats a dangerous road to go down in any industry, but one this industry specifically has tried to shove down player's throats time and time again (OG Xbox One as another massive example).
I still use sales like this to pick up super cheap versions of games I'm interested in, I'm not some kind of ideological purist who thinks Steam can do no wrong, but for people who are actively invested in not just PC gaming but the Steam ecosystem having a major industry player specifically align themselves to attack the consumer benefits of that ecosystem is super fucking shitty.