Not sure what size companies you're used to working for, but every large company over 5,000 employees that I've been with since 1997, HR *does* make all hiring and firing decisions and "managers" are responsible to simply "manage" their resources.
Yep, that's why it SUCKS to work in a big company in America these days.
Yes, I know exactly who decides who gets hired and that is why I am against them being allowed to do so.
One hire was a young lady who had the most annoying voice it has ever been my misfortune to hear. We were taking orders by phone and her shrieking would drown out what the customer was saying. It was no surprise that order errors shot through the roof.
They decided that it would be wise to hire a militant vegan for a department that had opening day as their floating holiday.
They hired a germa-phobe to take blood samples from livestock.
I left HR in 1991...worked high tech...IE Intel, etc during extreme growth...at the time I left HR was becoming like a govt bureaucracy...hated it...can’t imagine it now.