There are also packages available through AUR/homebrew and the like: https://ops.city/downloads .
The script is only there facilitate the 'install' such as ensuring you have qemu installed locally or assessing whether you have kvm/hvf rights/etc.
Also, I don't think this is documented yet but you can target various PRs/builds with ops via this way:
ops run /bin/ls --nanos-version d632de2
Things like this shouldn't be 'easy'. they should be well-documented, sane and safe. This is certainly an interesting and novel approach to tackle some of the absolute mess Docker has made of the world, but at the end of the day, if a system is compromised, its compromised, whether that be the docker user or the kvm/hvf group members.