The important thing is not that HN gets "better" according to your preferences (which appear to differ from those of the moderators), but that you have a community that more suits your preferences.
In a similar vein, you can complain as much as you like that company x's smartphone doesn't have the features you think are important, or, better, you can buy company y's smartphone that does.
Given that, yes, you should find a community whose leadership agree with your perspective.
Average users really have no say while they're here. There's no real ability to control or even influence how this site is operated.
Leaving, or choosing not to actively participate any longer, probably does have the biggest impact of all of the options available to a user. Discussion forums need participants, and participants leaving over time can have a huge impact.
Slashdot is a good example of this. Various site owners/operators started changing things in ways that users did not like. Many users spoke out, but they were ignored. In many cases, they were subjected to downmodding, especially those who spoke out against bad UI changes or the recent beta site. Seeing that discussing the problems had no impact on the situation, they left. Now Slashdot is a wasteland compared to what it once was, a decade or so ago. The decline in participation may be gradual, but it's very real, and its impact is significant.
I have to take issue with this. We change decisions all the time because of what users think, and I've left many records of that in the threads. HN moderation is really a collaboration between us and the community.
What HN isn't, is purely driven by votes. If it were, the front page would consist of outrage, gossip, and fashion. Those are the things that reliably get upvotes regardless of how substantive they are.
What I mean, for example, is that while submissions and comments may be critiqued, there's pretty much no formal way for users in general here to critique that critiquing. The best that can be done is a submission like this one, which for whatever reason ended up off of the front page rather quickly. That's what I'm talking about.
Slashdot has its meta-moderation system, for example, which is somewhat useful and somewhat accessible. There's nothing even approaching that here, as far as I know.
So it seems as if leaving slashdot did not really make it better. I'm not aware of a reincarnation that kept the good bits, either. So, to put a sharp point on it: just because blowing a city up has a "bigger impact" than being in it and complaining, doesn't necessarily make it the better option, if you know what I mean?
It may not be an ideal situation, of course, but it's better than the problems continuing to build under the surface, and users remaining miserable.
Now that the discontent is much more visible, there's at least some hope that real improvement may just happen there. That would not have been the case if people had remained, even if they were merely just vocal about their discontent, without acting upon it in some measurable way.