I love GitLab, and I use a private instance at work, but I won't use it to store my public projects for one sole reason: you can't hide your email address shown in commits.
This seems a little off-kilter. If you're that concerned, set a dummy email address in your "~/.gitconfig", or your project-specific ".git/config". I mean, I could just clone the repository if I wanted, and if I wanted to scrape it I could certainly do that too.
You can have multiple addresses associated with your GitLab as well, so you can add the dummy one to make sure your profile metadata still shows up.
You can't hide it on github either. You can just look at the commits directly, and I've used this to contact people in the past due to the "UI" hiding it. It's nothing more than the thinnest bit of obfuscation, and easily overcome.