Based on previous experience at a SV "unicorn", more often than not, a ton of work was not done. The "specs" were vague and poorly written. "Lacks attention to detail" is how I would describe most PMs at that place. I think they had a 1:1 ratio of PMs to engineers.
I was only slightly exaggerating. Though I do remember being in my daily standup, and regularly there were 3 engineers, a dev manager, 2 PMs, the product directory, and a designer of some sort.