Epic may still make games but they are primarily FTP these days, so that argument goes out of the window frankly. Also there are quite a few examples of Steam games that are Steam only. Valve may not force it on the developers but there are nonetheless examples of that, one being StreetFighter V which uses UE4. Is it fair as a consumer that I can only buy that game (for the PC) on Steam? (Which by the way they take 30% of the cut). I don’t see Epic having a go at Valve for that.
Anyway we are going round in circles, In the end I’m not saying that Microsoft should go down this route, all I am saying is that they are entitled to and Epic screaming bloody murder in the way did is not helping the situation, and is rude at best, hypocritical at worst.