There are tons of devices used that have no built-in BMC (like the Thinkpads in the original comment in this thread), yet still need reliable remote control in certain cases (e.g. a remote lab, or multiple-unit headless testing).
It would be a bit odd if a place was deploying new Dell servers and slapping IP KVMs on top of them.
OK, I just don't see the intersection of people/companies that are using thinkpads in their server room and those willing to pay $400 for a KVM being too large
Surprising amount of gear required extra licenses or even parts to have fully functional remote console that does all the stuff PiKVM 4 brings to the table, and not always do you have the benefit of properly operational netboot infrastructure (especially in corporate settings with their usually broken by design networks) - and remote boot media might be gated behind license.
So you end up with ipkvm because there might be windows server that requires remote display, or because for various reasons IPMI SOL or equivalent does not work properly (BIOS mode enabled instead of UEFI, SOL requiring extra license, etc). Or even not being able to setup autoconfiguration for BMC but for various reasons it's easier to setup ipkvm.
TBC I don't necessarily mean they're using them on those servers. Just saying the prices are peanuts to them. I find KVMs are usually used for non-rackmount / weird hardware that nonetheless ends up in a server room.
It would be a bit odd if a place was deploying new Dell servers and slapping IP KVMs on top of them.