I think I’d be suspicious of articles about a country edited by nationals of that country if Pew Research shows that country as having relatively high national pride. Usually, that manifests in an attempt to avoid shame by altering representations of reality rather than being secure enough to handle reality.

An example of something I encountered was that many articles on India in Wikipedia were written in a manner that is sort of child like, aiming at grandiose claims and conspiracy theories. It was obvious, reading from the outside, that it was nonsense.

Anyway, in general I find a English language Wikipedia pretty good where there is a lot of traffic but it looks like the rarer articles are where random people assert their propaganda.