Valve ... is unfortunate. They have done really good work for gaming on Linux. But even if they are eternally good-willed (which already seems a bit much to describe the current state, and I assume this will take a sharp downturn once Gabe Newell is not in charge anymore), they are US-based and that carries inherent risks.
Workers & Resources is made by a company from Slovakia. Unintentionally, all the games I play were all European anyway. And if they weren’t, I pirated them.
Plenty of good indie games made by EU at least. I mean, story driven punch and click (as the steam page description calls it) games like Brok the Investigator (from the French Cowcat Games), short but good enough games like Super Algebrawl and Shotgun King (from PUNKCAKE Délicieux), fun somewhat old-school feeling platformers like Cavern of Dreams (published by London based Super Rare Originals (couldn't find where Bynine Studio is from, though)), etcetera.
From Germany:
The Gothic, Risen and Elex role playing game series..
The X series (nothing todo with twitter)
With the latest game being X4. Steep learning curve but crazy good afterwards.