This is a page on internal Wikipedia policy, so there is no question about the accuracy here. The parent comment was pointing out that, in principle, Wikipedia policy is that contributors do not "own" content on Wikipedia in the sense of having a right to refuse edits to content that they contributed.
On the contrary: Wikipedia users are just as much (if not more) subject to their own wishful thinking and dirty politics when writing internal policy pages as they are when writing regular articles. Especially that there is no requirement to cite sources for the former. The policies as written may fail to reflect how editing actually looks like; hell, they might even not be actual policies at all. A single person could slip a passage in a policy page that supports their own opinion without anyone else noticing, and later cite that passage as if it were authoritative. (Or imply authoritativeness by simply placing a mere 'essay' in the Wikipedia namespace.)
Nobody cares what should happen 'in principle' unless the principles are enforced — which they are often not. See for example how the enforcement of the verifiability policy looks like.[0]
Are you seriously trying to persuade someone who has doubts about the accuracy of Wikipedia content with a link to a Wikipedia page?