To be honest, if you really need Windows servers you should run core if possible. Basically all Microsoft’s management shit can be run remotely from your jump/management host. That said a lot of shit requires gui and refuses to run on core, like adsync
There’s slight difference in resource usage of course, which does scale if you’re unlucky enough to have lot of them.
Minimum ram required is 512mb for core, 2gb for desktop experience so we can safely assume keeping the gui usable eats some 1.5gb memory. 500 servers adds some 750gb overhead in theory.
Then there’s of course the fact that less bloat will generally add up to less problems. Ever rdp to a server and start menu refuses to open or other weird gui shit. That’s just wasting your time.