@Syd: any good manager can cut people in less than a week. It doesn’t take much to see who is doing poorly, especially if we are talking about entire departments.
As a manager I have always fired or at least highlighted to upper management every poor performing employee in my report within a week. You just look at who got hired without actually knowing the subject matter, ask other team members about the dynamics within and who they think does very well and does poorly, people that do poorly are generally well known, they are a drag on others, they think they are the smartest, they think they know everything, they micromanage, have various complaints against them.
First thing to look at is their goal: DEI and HR can be cut without any negative impact out of any company. Seriously, what do they even do that brings profit? If you have a legal issue with an employee, you should ask the legal department which is what HR does anyway. Any manager that relies on HR to handhold employee issues with them is part of the problem.
Next big thing is to look at finance: are there any groups that only exist to move money internal to the company. If so, they are not bringing any value. If the money you move does not move corresponding in a bank, it is Monopoly money.
Then the one after that is any group that replicates work that a database or IT system is already doing. You see people taking Excel out of system and making reports and statements out of that manually, you are redundant, your job does not need to exist.
Then there are those that do PR, marketing, sales etc. If your group is not involved in making the product better or taking feedback from customers, you are a net loss, cut it and be gone, sales people today still think cold calling and email campaigns sell product. Not true.
Next is government liaisons and customer account managers. You cannot legally affect anyone in government, likewise you cannot ethically reward specific people in a company to buy your product. I know account managers spend an inordinate amount of resources in comparison with the expenditure of the clients.