I think you're reading too much into it. Gitlab's "personas" just seem like a slightly cutesier version of the bog-standard "user story" technique[1]. They've also been around for about 30 years (from a search, I wasn't aware of this before)[2].
[1]: https://en.wikipedia.org/wiki/User_story
[2]: https://en.wikipedia.org/wiki/Persona_(user_experience)