Microsoft, EA and Ubisoft eventually caved in and offer their games also on Steam.

EGS "exclusives" are usually timed exclusives. You wait half a year or so, and get a more stable, better optimized and usually also cheaper version on Steam too. If you want to play an EGS exclusive game immediately, installing EGS isn't a big deal either.

So far, having multiple competing app stores on PC has been a win both for users and developers. Choice is always a good thing.