You don't, you can compile from source.

Unreal is a top class engine. Yes, it's proprietary and you always have to be cautious, but right now, it's an engine that delivers top features that can build great games and isn't run by Unity. If you win big, you need to pay, but you know that going into it.

Godot is great and improving all the time but it needs maturity.

It was a head vs heart decision and the head won this time.