You wouldn’t ship your game with built in editing tools from the engine. Those editing tools are not restrictive enough to just hand out to the general player base. They’re too powerful and too hard to use.
Maybe, but this isn’t remotely common with existing open source game engines.
Modding a game engine’s editing tools to the point where they are user friendly enough for your players is almost always a bigger challenge than building basic editing tools using the engine.
This entire argument is insane to me. Someone is releasing something for free with the caveat that you can’t use it for this one specific very uncommon thing. Then people are up in arms “what if one day I want to do this one specific thing? Do you? No but what if I did?” Don’t use Defold.