My understanding of your comment is that "free software zealots" are people who belong to the "free software movement" [1]. If that's correct, where did you get the impression it's "a tiny fraction of the open source community"?
This article [2] from 2022 states that 22% of software project have a copyleft license. Is that a fraction you'd deem "tiny"?
I'm a free software advocate, but I'm not a free software zealot. I think nonrestrictive terms of use is the only way to remain ethical. However I'm also a pragmatist and understand the value and use of non-free software. Zealots famously allow for no such exceptions.
Another example There are a number of "rust zealots" who believe it's a moral imperative to rewrite all software in rust, and any who disagrees is immoral and acting in bad faith. Similarly the number of people who are rust zealots are a small fraction of those who like and advocate for rust.
