The thing with this is: its just a symlink to the systemd-run binary, which talks to PID1 to spawn new processes (in separate cgroups IIRC). Its one of the most fundamental parts of systemd. Even the debian systemd package includes systemd-run.

I guess the other question is if some tools the distro provides might switch to supporting it by default. For example on Arch there is makepkg that should never be executed as root, but does internally call some things with elevated privileges (mostly pacman to install and remove packages). Currently it checks for sudo and if not falls back to su, but maybe it might be worth considering changing su for run0 if its guaranteed to be there.