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.
This sounds pretty annoying though: https://docs.gitlab.com/administration/license_usage/
I'm not sure, you'd have to check their pricing pages.