Not sure where you are getting your data for DOTA 2, a player only has so many reports they can submit in a certain time frame. There have been plenty of times someone said they "Reported" me because I accidentally messed up on something, but no official action was taken. And only maybe two or three times has an action been taken against the dozen or so people I have reported.
So while the players do have "Power", that I guess could be "Abused", it is in no way ultimate or far-reaching. I rarely see trolls on DOTA anyway, like I said, I have reported maybe 12 people, out of what like... 800 games or so? I do not recall my numbers, sorry.
And as for CSGO, I have no idea what that is, so I cannot speak to it.