Looks like gentoo's pulled "cmake-utils.eclass" out from under you.
[4] "plex-overlay" /var/db/repos/plex-overlay (cache: parse|ebuild*3.0.24#metadata-md5#metadata-flat#assign)
Reading up to 170 categories of packages... * ERROR: media-tv/plex-media-player-2.57.0.1074::plex-overlay failed (depend phase):
* cmake-utils.eclass could not be found by inherit()
*
* Call stack:
* ebuild.sh, line 618: Called source '/var/db/repos/plex-overlay/media-tv/plex-media-player/plex-media-player-2.57.0.1074.ebuild'
* plex-media-player-2.57.0.1074.ebuild, line 6: Called inherit 'desktop' 'eutils' 'xdg' 'cmake-utils'
* ebuild.sh, line 264: Called die
* The specific snippet of code:
* [[ -z ${location} ]] && die "${1}.eclass could not be found by inherit()"
*
* If you need support, post the output of `emerge --info '=media-tv/plex-media-player-2.57.0.1074::plex-overlay'`,
* the complete build log and the output of `emerge -pqv '=media-tv/plex-media-player-2.57.0.1074::plex-overlay'`.
* Working directory: '/usr/lib/python3.10/site-packages'
* S: '/plex-media-player-2.57.0.1074'
Looks like gentoo's pulled "cmake-utils.eclass" out from under you.