LaTeX, like many applications, does search its “packages” from multiple locations. The content from RPMs is in system directories. Ideally, all “texlive packages” are available as RPM packages (but EL is not comprehensive). There might me chance to set up additional location for “site” or “project”, and then there is the ~/texmf. Each user can put their own content there. I have long forgotten the exact syntax.
[el9]$ dnf list texlive\* | grep -c texlive
373
[el9]$ dnf --enablerepo=epel list texlive\* | grep -c texlive
433
and none of them provides the “comment”.
[el7]$ yum list texlive\* | grep -c texlive
550
[el7]$ yum --enablerepo=epel list texlive\* | grep -c texlive
666
EPEL 7 has texlive-comment and texlive-comment-doc.
In other words, EPEL builds “comment” for el7, but not for el9.
The appropriate action is to create EPEL request for el9 version of texlive-comment (and other missing packages).