I work in games, the reason it works the opposite for them is because Unreal Editor is a product that is also shipped.

Sadly for most of us, the tools used to make the game (that includes the engine) are for internal use only, and most of the time there is no army of programmers available to do all of the work ahead of time. So it pays to wait and focus on the hot path used by the game you are shipping right now and not a hypothetical one you might ship later.