The zealot's standard rejoinder is that
everything is political. See, also, you're either with us or against. What contemporary liberal politics has brought to the table is "science" that purports to show a simple, direct link between rhetorical opposition or even mere abstention, and directly consequential, imminent harm. See, e.g., claims re trans-gender suicides, or just today insinuations that compromises made in the recently passed Inflation Reduction Act will kill minorities--
https://www.npr.org/2022/08/17/1117725655/the-spending-bill-...These are liberal analogs to, e.g., conservative claims about the how Civil Rights Act would directly lead to blacks and latinos raping and murdering whites, or in more recent years similar insinuations (and sometimes outright claims) regarding border controls. When you can draw a straight line between abstract policy preferences and the imminent death of an untold number of people, dissension becomes intolerable. Most people tend to agree with that sentiment on its face--that's why political rhetoric so often regresses to such stark terms--the sticking point is what that line looks like, if it even exists at all.
EDIT: I keep forgetting that the misuse of science is nothing new, so liberals aren't actually bringing anything new to the table in that regard. Of course science (certainly poor science, yet sadly mostly only in hindsight generally recognized as pseudo-science or non-science, e.g. Social Darwinism) was used to justify those example conservative claims, as well countless similarly specious claims from across the political spectrum going as far back as one cares to look, but particularly after empiricism displaced both institutional religion and rationalism as the fount of categorical truths.