I realize I am in minority, but for me, if project uses a mailing list I am more likely to do a drive-by contribution (compared to no contribution at all). Just doing git send-email is much easier compared to figuring out how to create whatever pull request is called in whatever forge the specific project is using.
Which, for drive-by contributions, does not really matter. It is a problem for long term contributions and project managements in general, true, but there often is some tracking system present (patchwork, debbugs, ...).