External Review References
These are some of the sources we've used to compare Trac and GitLab
Gitea - Alternative to GitLab and GitHub
Sure you CAN use git without a web UI, We had that at work for a while and it was not a good experience at all compared to using gitlab which we have now and we now have so many features that let us get things done faster.
GitHub Alternatives (Free, Paid, Self-Hosted)
GitLab statistics shows that a lot of repos have been imported from GitHub in past few hours.