Company of Heroes 2 was top seller for quite some time. Iirc, Noun even said they had 100k unique players roughly each day.
Besides that, steam is not the center of the universe when it comes to sales. There's alot of different retail stores & other websites. (There were alot of websites that offered a really good price) that you're not accounting for. I believe even it was Noun that said that CoH2 sold quite well in matter of fact.
Noun has a vested interest in making everything around CoH2 sound great.
Because Noun works for Relic.
I remember hearing how great everything was at THQ.
All players must connect through Steam. Currently, 6,000 are playing.
Look for Sega and Relic to react accordingly.