Sorry about that. I've updated the package now, and will be disowning it. I'm not using Arch as my daily driver now, so I am not in a position to maintain any packages.
Request #18726 has been rejected by diabonas [1]:
A missing conflict on the non-VCS package and a suboptimal pkgver()
function don't warrant a blanket deletion of an otherwise potentially
useful package.
Note that the maintainer has actually responded to the comment from
2019-08-20 requesting to add a provides for the non-VCS package on
2020-01-18, but seems to have overlooked the request to add the
corresponding conflict from 2020-01-17. Please make more of an effort
to contact the maintainer (in the package comments or directly by
email) before filing requests.
[1] https://aur.archlinux.org/account/diabonas/