Because the games are in the same genre and are often compared to one another. It is only natural to compare viewership as well, especially given how Valorant fans keep calling CS dead lol
I think is not dead. I feel is Valve fault that havent a big improvement to the game that will keep normal players to play the game? You can compare them but is like a hate type of comparison.
The lack of change is mostly due to the fans and not Valve. Whenever the weapon balancing or maps are changed they get ranted at for weeks. I suppose that is only natural for such an old game with long-term fans