Imagine using this energy for actually productive change, over being angry that you're being slightly inconvenienced.
Pretty much what happened is it wasn't advertised that you would need an epic games account to play the multiplayer, and people are angry about it for some reason. Likely because it's Epic, not because they had to make an account, though knowing Gamers they probably would be pissed about about having to make an account outside of steam too.
And it's funny because the one discord server I usually hang out on that has pretty chuddy people on it largely had a reaction of "Sure it sucks, but there's a lot bigger fish to fry in the games industry."
Uplay and Origin are the absolute worst, with both just constantly failing to do the literal one singular thing they're supposed to do. At least Epic actually functions consistently, about on par with Steam in my experience. But then I've had an account and been using the launcher since long before they had an actual store on it, back when it just had separate tabs for the UE4 editor (what I was using it for), Unreal Tournament, something called "Shadow Complex" that was some free sidescrolling UE4 tech demo or something, and the Paragon closed alpha (later joined by the Fortnite closed alpha).