Why do you needs so many cores for? Apache threads? Any old school wizard here?

I used to run many hosts with 28 cores per host. If performance scales, it's nicer to have a few 288 core hosts rather than a few hundred 28 core hosts.

Getting the performance to scale can be hard, of course. The less inter-core communication the better. Things that tend to work well are either stuff where a bunch of data comes in and a single thread works on it for a significant amount of time then ships the result or things where you can rely on the NIC(s) to split traffic and you can process the network queue for a connecrion on the same core that handles the userspace stuff (see Receive Side Scaling), but you need a fancy NIC to have 288 network queues.

Host it in proxxmox, run 8 different services on it each with 32 cores.

Yeah, virtualization, many (small) containers / VMs.

These almost always run many smaller virtual machines on top of a hypervisor. The target market is large enterprise or hyperscalers like the public clouds, Meta, etc...

data processing