I respectfully disagree; I do not believe that a large server list discourages a great deal of potential players from joining, nor do I believe private servers are at fault for the recent decline in players. In fact, I'm pretty confident that the decline has been due to the amount of bug abusers generally seen on any server. With the current lack of tools, it is not easy for an admin to check to see who is clipping through walls or duping items, which means that even if official servers were brought back up and private servers were taken down, there would be no change, other than the potential to drive even more players from the game.
Personally, I haven't played a whole lot recently due to getting rather bored with the game. Let's be honest, there isn't a whole lot of content in the game yet. I'm not done with it, I'm just waiting for more stuff to be added. Every update I might jump on from time to time and glance at the new stuff, but other then that, I'm just biding my time for a more polished game to form.
I will agree that it is very easy for the admins of rented servers to abuse the current command system, but I've seen servers with high abuse lose their player-base very quickly to those who don't. I've also seen servers with rather loyal administration that try their best to keep their small community happy.
Keep in mind the game was a much better time before Private severs were added. Rust had more bugs, more dupes and less content. While you might be getting bored with the game that is an entirely different story, this is about how private servers are hurting the game. While you might think they are hurting it much less that what i am saying, and i respect that, it is hurting the game no matter how you look at it.