Free offerings are a marketing expense via extended trial run. It is more productive for society to give away limited product offerings at little marginal cost than to put the equivalent into more advertising, salespeople, and influencer campaigns.
If I want to find out which git hosting to use, it would be great to try out Gitlab, GitHub, and Bitbucket first (and everyone else try them) so we could assess genuine product usefulness as a group rather than rely on Twitter ads or astroturfing here (no bearing on product)
You can excuse or justify it however you want. But it's still false and deceptive advertising to use "free" in situations like this.
To say some service is "Free" (for now) means you're paying something that isn't disclosed. Even if you're paying in time as beta-tester, you're still paying. And you're still paying in data.
Whereas, GitLab on-prem install is largely under MIT license, which is widely considered to be a very permissive license. I could see the FTC coming to similar agreement with that statement.
Demo is interesting, although it nearly always implies limited functionality and/or limited timeframe you can use the software, which may be misleading for some free tiers.
Freeware could be a good term, but wouldn't it still have the same nothing-is-free issue that GP brought up calling it "false and deceptive advertising"? The term certainly doesn't connote the "why" behind the offering
If I want to find out which git hosting to use, it would be great to try out Gitlab, GitHub, and Bitbucket first (and everyone else try them) so we could assess genuine product usefulness as a group rather than rely on Twitter ads or astroturfing here (no bearing on product)