While I don't think Riot completely ignores feedback every time they release a feature, they do tend to stonewall feedback on any sort of big addition that enters the PBE, and even after that problematic feature gets released to Live, they continue to defend it for an extended period of time. Part of it does stem from a legitimate concern: any sort of game feedback forum skews negative, and many of the players complaining about a feature on the PBE haven't tested it yet, so they do expect their features to be complained about even if they do turn out successful. However, I feel Riot takes it a little too far, and simply assumes that all of the complaining is unfounded and malicious, even when it comes from players trying to help. Additionally, I think to this day Riot still doesn't really understand how sample sizes work: spaces like Gameplay and Reddit are continually dismissed as only a small fraction of the total playerbase, and therefore unimportant, while also failing to mention that these are nonetheless two of the largest communities that consistently give detailed feedback on League. This is why it often takes Riot months to go back on features that have been nearly unanimously criticized across practically every League-related internet space.
In general, Riot's communication strategy has become increasingly distant and opaque, and as a result the bond of mutual trust and respect that was once central to League's player-developer relationship has severely degraded over the years. Rioters routinely mention that they do get feedback from reliable sources, but fail to mention what those sources are or how we can access them, let alone give any sort of indication to the average player on how their voice can be heard. As a result, we players often accuse Riot of being out of touch and destructively selfish, which I think is largely untrue, but I feel Riot also has been treating players less than respectfully, going beyond simply defending their work, and outright belittling and disenfranchizing players who make valid complaints. We saw this recently with Riot's stance on BE, where they completely ignored how most players felt about the milestoning of currency, and instead pretended for a while that everyone was wrong simply because their (flawed) math told them that currency gains had increased across the board. There is a massive amount of work that needs to be put into reestablishing proper communications channels, which should likely include an overhaul to Gameplay, but it doesn't seem like that's a priority right now, even though it should be.