There is no point in having moderators if they can't act unilaterally.
In all but this meta site, moderators are elected by the community because of their reputations and ability to make reasoned decisions. There is also a need for them to handle some obvious things (at least to most moderators, if not most users with years of experience) quickly. This helps the overall site run more smoothly.
If other people think that a question is closed incorrectly, there are already ways of democratically addressing that: if enough people vote to reopen a question (those who have earned that right), it will be reopened. And this will happen regardless of any particular moderator's input.
People can also question the closure at the meta level, where other moderators can see the discussion and (at their own discretion) reopen it. If several moderators see the discussion and choose not to reopen it, it's probably a good indicator that there isn't a compelling argument to have it reopened. (And while it can be frustrating for one person to disagree with many, that's how a democracy functions.)
A case can be made that some questions have been closed inappropriately. And some of those have been reopened in one way or another. But the number of those that have been closed for good reason outweigh those edge cases. Removing the ability of moderators to close questions that shouldn't be open would do more harm than good.