This is a complaint that people make about the U.S. system too. I think it’s misplaced but I think this dispersion of power is one of the strengths of the U.S. and Bitcoin systems. Again, the U.S. founders were extremely wary of populist/popular movements, i.e. the whims of “the little guy”. You can see how important this is in a system like a cryptocurrency since there are very few people on twitter/reddit who are decrying one position over another that have read the code and understand the implications as much as the core devs, segwit2x devs, miners, and economic actors such as exchanges or businesses.
But yes, to more effectively have your voice heard, you just need to run a full node and then the version of the code that you run (and the transactions/blocks you validate) count as votes. Just as you can protest all you want in the U.S. but you actually have to vote and lobby your representatives in order to push policy in a specific direction. A UASF is only possible because of this, but users voting with their nodes alone is not enough because of the built in checks and balances, and this, I believe, is a good thing because it means you need broad consensus from all/most of the branches to enact changes.