You are right that science has no obligation to give every crank theory equal time. Climate denial does not become a coequal scientific position just because someone demands “balance.” That is exactly what sensationalist media and cable news (looking at you, Fox News) has been doing for decades—fooling low-information viewers into thinking crackpot conspiracies belong on the same stage as rigorous scientific research. On that point, you'll get no argument from me.
But you are smuggling in a false dichotomy. The alternatives are not “scientific truth” on one side and “social-media shouting” on the other. Science is not Twitter with lab coats, but it is still a social process. Peer review, replication, conferences, journals, grant fights, disciplinary norms, consensus formation, and paradigm shifts are not decorative plumbing. They are the machinery.
If you haven't read "The Structure of Scientific Revolutions" by Thomas Kuhn, this a really good point for you to pick it up. If you have read it, then I would suggest you need to re-read it. Science is fundamentally a social process. It was Kuhn’s central insight. He did not show that facts are democratic, or that electrons take a caucus vote before tunneling. He showed that what counts as a good question, a valid method, a decisive anomaly, or an acceptable explanation is mediated through scientific communities operating within paradigms. The objectivity comes from the discipline of that process, not from pretending the process does not exist.
Wikipedia is even more obviously social. It is not a laboratory and it is not a journal. It is a consensus-driven encyclopedia that summarizes reliable sources under rules like verifiability, due weight, and no false balance. That means the climate denial article should not pretend denialism has the same standing as climate science. But it also means “Wikipedia doesn’t debate” is an absurd claim. Wikipedia is practically made of talk pages, RfCs, noticeboards, policy arguments, and edit wars with footnotes.
Truth is not democratic. Fine. But Wikipedia's neutrality is negotiated. If that negotiation is disciplined by good sources and due weight, it can work. If it is captured by factional editing, rule-gaming, or selective enforcement, then calling it “science” does not cleanse the problem. It just gives the hive mind a lab coat.