Epic is more than capable of putting out content worth coming for, Already UT, Paragon, A place holder for Fort Night, And a tab for modding tools (for Ark) already exist on the once solo purpose Epic Launcher.
Also just like many of the other companies out there you can support multiple launchers. No reason a person cant allow customers to come into the Epic ecosystem through their favorite launcher (most often steam).
Numerous titles on steam install and launch through their own launcher.
I personally would love to see something like what is being described above, In fact its what i always thought should be the case from back before i even knew how it actually works. Trying to deal with things such a either building your own backend or using someone else. Such as. Playfab, or Gamesparks can be highly frustrating. As those services often dont maintain their API for UE C++ much less UE Blueprint. Having a engine specific use case i would think it could highly beneficial for us 3rd party guys, As well as EPIC own internal use.