If it's humanly possible to do in godot, yes! I think it's important to get software running on non-proprietary systems.
The html5 demo was make in godot 3.5, and I've been updating the downloadable along the 4.0 betas and release candidates — which is why I haven't been able to update the html5 version, the 4.0 html5 export still is very buggy.
Incidentally, I made the call last week that I'll be remaking the project from scratch in 4.0 to drop a lot of baggage from that updating process and bake in better assumptions in how content is structured. Being able to copy over the code from the demo is making it go a lot quicker than the first time around.