NetBoot - a nail in the coffin?
Apple have updated the following articles:
Create a NetBoot, NetInstall, or NetRestore image: https://support.apple.com/en-gb/HT202770
Mac startup key combinations: https://support.apple.com/en-gb/HT201255
The following parts stick out in particular:

…and…

I believe NetBoot is no longer possible on an iMac Pro, even if you disable Secure Boot, as outlined here: https://support.apple.com/en-us/HT208330 - I haven’t actually got an iMac Pro to test this on, so if anyone could confirm, that would be fantastic. I’m also not sure if Internet Recovery (https://support.apple.com/en-gb/HT204904 and https://support.apple.com/en-gb/HT201314) works, but assume it does as Apple haven’t updated those articles (yet).
The 2.6 release of Configurator adds functionality to recover iMac Pros, in a similar fashion to a DFU restore on iOS devices: https://help.apple.com/configurator/mac/2.6/#/apdebea5be51
It’ll be interesting to see what happens with the next round of Mac releases… interesting times indeed…