1. The engineering management, most of them joined right out of university in around 2018-2020. They were then elevated into "manager" positions within a couple of years and "director/VP" positions in perhaps 4-5 years (maybe even quicker?). I suspect the CEO did this as a retention tactic. Tons of other reviews cover all this entails so you can read those accounts for more information and come to your own judgment.
2. Many of the people who joined and were competent over the years (i.e. did a lot of heavy lifting) have left for greener pastures. I would expect the exodus to continue. By the end, they'll be left with the scraps.
3. Compensation, to my recollection it's similar to traditional defense companies (not accounting for any benefits). Compared to rising defense startups it's on the more underwhelming side.
4. The company uses timesheets to track and bill hours, so it seemed there was an incentive to keep, or grow employee bloat and move quality further down the priority chain. Some of this was reflected in their hiring. Management inexperience, or even insecurity, possibly played a role in this. I do think if the company shifted business models, it could reasonably get by with fewer engineers, assuming they are competent.