Earlier quoted context omitted.
I think three.js is that. - All of the above except language - Library rather than engine I've had really good luck with it versus Babylon or Unity.
Let's be fair to three.js, the comparison would be to aframe. https://aframe.io/ or similar projects. (Godot Engine Maintainer)
You are right, though I think all three can be compared, depending on the type of project. Unity is on the decline and I would be happy for Godot to become the future for those types of games.