This is status-bydesign, not a bug. Only posts with negative score can be deleted outright by trusted users; see the trusted user privilegetrusted user privilege:
Trusted users are allowed to perform trusted actions, including:
- Voting to delete answers with score of -1 or lower
Emphasis mine. In the Low Quality Review queue that limit is raised to 0 or lowerraised to 0 or lower to save you having to downvote first. But this still means that if the score of the post is 1 or higher, even trusted users only get to recommend deletion.
For example, I have 20k+ here on Meta, but for this reviewthis review (post visible to 10k+ only) the post in question had a score of +2 when I voted to delete, so my vote was recorded as a recommendation rather than an outright deletion vote.