Disclaimer: I've worked with Sid and his team in the past.
Few people realize how long it's been since GitLab was a simple clone -- there has been a ton of legitimate net new innovation, and that happened under Sid (and of course all the awesome people working at GitLab).
Another thing that's actually insanely under-discussed is how openly GitLab runs and how that's been a successful model for them. I'm not sure I know another open core company that has been so successful in the space of developers who bend over backwards to pay nothing and spend hours of their own time (read $$$$$) to host their own <X>.
IMO they are the only credible competitor to GitHub, and they're open core, huge open source orgs, small companies, and large companies trust them (rightfully so), and they've built this all while being incredibly open and to this day you can still self-host their core software (which is a force multiplier for software companies).