When I visit https://ru.wikipedia.org/w/api.php?action=query&format=json&prop=pageprops|langlinks|langlinkscount&generator=mostviewed&ppprop=wikibase_item|disambiguation&gpvimlimit=500&lllang=uz&lllimit=500 I get
{"batchcomplete":""}. This issue persists even when I change the gpvimlimit to any other value.
I have seen this issue happen with enwiki and uzwiki at times (not currently).
Refs: T216750: Article recommendation API: replace WDQS with MW API