(Why is it these kinds of discussions get snotty so quickly?)

I don't know how else an end user can express their preference.

IP addresses are PII under the GDPR with enough context - although honestly I don't want to go down that horrible rabbit hole.

But sure, sure, the site operators can do whatever they please. It's just Plausible banging on about being privacy friendly and ethical seems a bit ironic and is frustrating to see.

Edit: The DNT flag is explicitly ignored by Plausible as well: https://github.com/plausible/analytics/discussions/646