Here's something interesting, Epic Games are launching their Epic Online Services and it will support Linux as well as multiple different game engines.
Building upon the work they've done with Fortnite, it's going to offer support for: Parties, an in-game Overlay, Matchmaking, Player reports, Achievements, leaderboards, stats and so on. Don't get too excited though, as right now it's only offering Game analytics (telemetry about players) and a support ticket system with everything else "Coming soon".
On the official page that's now live, it shows the happy little Linux "tux" logo and in the FAQ at the bottom it clearly states it too:
Epic Online Services will initially come with built-in support for Windows, Mac, and Linux. PlayStation, Xbox, Android, Switch, and iOS support will be added in the coming months.
Regardless of your feelings towards Epic Games and their current exclusive deal strategy, it's still essential that services like this support Linux. Lots of developers use the Unreal Engine which they will no doubt push for developers to use this, also since it will support Unity, other games engines and other stores (So Steam is fine too) if even more developers use it then we don't want another barrier for Linux game development.
As for the Epic Store itself, don't get excited about that either, it's still not even on their (now public) roadmap.