Maybe once you have a lot of readers, but I can give an account of just being pushed around by ratings. I didn't do any promotion, so maybe some phony review swaps would have helped, but the only critical reviews I got were as helpful as a flying paper weight. They just jotted down a few random things, mostly contradictive or easy to deconstruct (i.e. review says something is not in the story, but it is in the story - doesn't matter if they like it or not, because they lied and said it wasn't there to begin with, instead of saying they didn't like it). Also, no comment on how those bad things are being bad and where, especially in things with a wide range of how they could apply (i.e. "character is inconsitent" - now, you would assume it's the protagonist, but in 100 k words, with x amount of characters, how would you really know what they mean and who they mean?). That is NOT helpful. The most helpful comment on that front was likely the dude picking out the few typos I missed.
My personal experience might not match with that of others, but RR is toxic af in my opinion.
Don't get me wrong, both can be helpful to grow a thick skin and maybe one has a bit of luck and finds the right readers. I just don't see how a beginner will do well on that site.