Disagree. Github's self-hosted product is trash compared to Gitlab. Plus they were very late to the game when it came to stuff like CI, package management, project tracking and a whole suite of enterprise features. Github had (and still has) a huge lead in public open-source development, but that's it.

While yes, my first usage of Gitlab was an on-prem install, things really took off with Gitlab.com in ways I don't think anyone expected with healthy competition from Bitbucket and Github. I do think it was the unlimited free private repos with unlimited contributors that really skyrocketed the success of the Gitlab.com path.

Anecdotally I’ve felt like most of the features GitHub has released for some time now are a clone of something that hit Gitlab first.

Github is initially B2B SMB and B2C and Gitlab is B2B Enterprise. 10% of Github employee are sales , 25% for Gitlab. I would say they are not even competitors

Gitlab was earlier/better at letting companies install a version on-prem.

Their CI story was also a lot better until Github added Actions

Still better I think. Actions are hard to use and ridiculously verbose.

Which part is verbose?

We have been happy customers for many years. It has been a breeze to manage and upgrades, backups, and DR have been very good for us. For an on prem software of this complexity it is quite a feat. It has also always been at a very reasonable and affordable price point for enterprise-y on prem software. As an infosec consultancy that used it for projects and code we always appreciated being able to manage the security of our installation.

I was able to get free unlimited private repos from github and bitbucket since 2011, but we still used the ancestor of gitlab as our local repo.