Structurally I'd say no. But I'd be concerned if they cared that little about other work that wasn't seen, but base that off other work.
They're just saving time by doing it rough, and if it's going to be covered then why bother wasting time making it neat.
I think it'll be fine once plastered over, but those seven rows with a consistent gap down the middle doesn't inspire confidence in the quality of their work.
Nah, but often you can tell how good builders are by the workmanship of ‘hidden’ or covered up work. Structurally that will be fine, just would like to understand the thought process, as there’s minimal pride in that. Like you say it will be covered, nothing to worry about in that respect.
What's the rest of the standard of their work like? Any other red flags? Looks pretty shit tbh.