Fundamentally, that's just git with a few common features like pull requests, account management and bug tracking.

Choosing one over the other is just a matter of details. How well it integrates with the corporate network, how pretty it looks, the options regarding CI/CD integration, overall popularity and community, etc... Last time I got to choose, I went with Gitea, because performance was good and it met my needs.

I found it much easier to organize repos hierarchically with GitLab. Permissions also seemed easier to setup.

Yeah I agree. There are only very minor differences.