It seems that Steam is in the middle of their spring autumn cleaning before the sales start. Hundreds of games have been removed from Steam in a short period.
A Reddit user, thomasthe1st, noticed that Valve is deleting a massive amount of games. Visiting madjoki.com’s Steam tracker will show nearly 1000 games that have been removed in the previous 24 hours.
Most of the deleted games are indie projects which you could only find information on the now deleted Steam pages for them.
Valve has been under a lot of pressure in the previous years to actually moderate the games available on Steam. The reasons ranging from cheap ports of mobile games, and questionable games that violate ToS to straight up asset flips developed to make a quick buck.