Steam stopped selling a lot of projects from Koch Media, which owns publishers and studios like Prime Matter, Deep Silver, Volition and others.
Their projects include:
Also, the game Pathfinder: Kingmaker from the Russian studio was removed from sale in Russia. But at the same time, Pathfinder Wrath of the Righteous remained, as it was published by another company.
Koch Media hasn’t made any announcements regarding unavailability of games yet. But even so it is clear that this is in connection with the “military operation” in Ukraine.