Totally disagree. I don't believe that the poker site cares who wins as long as they get their rake. the money has to go somewhere to someone so why should they care.
They care a lot. For example, when a super solid regular sits down, fish tend to leave that table and try to find a different one.
The reason they do this, is because they are getting crushed, to such an extent, that they don't want to play anymore.
At this point, some of them maybe elect to change sites, some of them may decide to write to the operator or post on various websites, about how the cards are rigged.
Some might just stop playing and take a break. Maybe a kid gets so mad, that he starts spamming the N word in chat and the operator has to ban him from the site.
Anyways, all of these scenarios, are very unfavourable for the operator, and can be mitigated by trying to reduce the amount of winning players participating on any given site.
This is also why sites try many different things. GG Poker has straight up been caught banning winning players lol.
Some of those things would be,
-hiding names
-banning HUD's
-having a high rake and weak sauce rewards (
888 Poker)
-making it against the rules to "bum hunt" (try to snipe weak players)
-preventing players from queing in a wait list
-PartyPoker even tried to have a MMR system (Match Making Rating)
These are all things, that Pokersites have chosen to do, just for the fact, of trying to bring in recreational players, while chasing away the good ones.
Then there are things I speculate on that aren't confirmed, such as...
-being denied a reverse self exclusion
-being denied promo's (I used to get 10% MINIMUM on any money I would put on literally any site if I opened chat support and asked, but ever since I started making withdraws and profit, I haven't got a bonus once.)
Anyways, the point is, YES they care A LOT lol.