That being said, I don't know if Riot is even listening to any of the complaints, since our population is dwindling in comparison to the vast amount of new players.
I think this can be more logically attributed to a benefit analysis rather than Riot not listening to complaints. If Riot has x amount of resources, what should they be used for to benefit the most players in the most significant way?
Pwyff made a good post relating to this recently:
Going off what I said earlier about self-perpetuating bubbles, it's tough to prioritize work on specific player needs when conversations hit such a critical mass that gauging concepts by passionate conversations means everything is a priority. In other words, once a conversation reaches more than a few hundred participants, it becomes A Very Big Deal to those players, and League has enough passionate players that this means every issue is now A Very Big Deal.
League of Legends' community is ridiculously massive, as we are all aware. There are a ton of issues that are, in the grand scheme of things, relatively localized. To the people that care about these issues they are a huge deal, but it's likely there's something else that's a bigger deal or otherwise more important.
Now. While this is important, I also think that there has been some pretty significant underestimation of how important a given issue might be. The LE skins thing was huge, and it was clear that there wasn't a ton of effort put into the solution. The opening of the vault was a pretty negative PR situation, and I think it was somewhat underestimated.