6 min seems about right for an enterprise server, the more you have like a raid card initialization the longer it will be. Since there devices are designed to be run for months or years without rebooting it really doesn’t matter that the reboot takes as long as it does.
iDRAC just lets you remote access the device and tweak bios settings or whatever remotely rather than having to use a physical kvm. I know dell and hp have utilities to let you modify bios settings from windows but I’m not sure if that extends to their server platforms as well.