Origin is actively avoided (to the point of avoiding EA's games completely), Ubisoft's Uplay will work with Steam, and Bethesda's launcher was immediately uninstalled after the debacle which was Fallout 76.
None of my friends (that will admit it, anyway) have the Epic launcher installed. They are all frustrated that games they're excited about ("The Outer Worlds" and "Borderlands 3") are timed exclusives on Epic's launcher.
Some of them are very hung up on the fact that Tencent owns a major stake in Epic Games (between 40%-50%). They have seen how China deals with games (WoW in China is the biggest one, game consoles not being legal in the county until recently) and the Internet (Great Firewall of China) and are in no way interested in allowing their software on the machine. Further, it has been observed that the Epic Launcher performs behaviors that behaviors they consider shady[1].
Personally, I won't play any games that are Epic Store exclusives. Not because I have any particular anger toward Epic (I've loved Unreal Tournament for a long time), but because I already have a large backlog of games on Steam, I'd like to keep everything in a single launcher, and by the time I have my backlog cleared, these games should be on Steam and a GOTY version will be out that has all of the DLC included, or if they're not, something else that I care about more will likely have come along.
[1] https://www.reddit.com/r/PhoenixPoint/comments/b0rxdq/epic_g...