The DDCUtil features of Powerdevil in KDE Plasma are currently disabled by default "DDCUtil library support is disabled by default as recomended by authors, add -DHAVE_DDCUTIL=On to enable" This is based on a conversation from 2017 where it was decided it was unstable.
I see work has continued on DDCUtil and on support for it in Powerdevil. Is it ready to be set to on by default? It is too late for Plasma 5.17 due for release in 2 weeks but we can tell distros the message is old as appropriate. Jonathan