Certainly Godot is the safer bet (probably why they are surging so much more right now), but Unreal is nowhere near as bad as Threads. Unreal is open source, and the license specifically forbids Epic from making retroactive changes like Unity just did:
The Agreement Between You and Epic
a. Amendments
If we make changes to this Agreement, you are not required to accept the amended Agreement, and this Agreement will continue to govern your use of any Licensed Technology you already have access to.