At hobbyist scale, it's usually more of a problem with assets rather than the engine itself, or with tools.
For example, in a game jam you might want to be able to push something to a public Git repo that anyone can pull from and build, and license it so people on the team have no question about whether they can share the code with other people. Easy way to do that is to have an agreement like, "Let's license our code under MIT and make the art CC BY 4.0. Agreed?" Then drop copies of the license text in the repo with everyone's name on it, and make the repo public.
As soon as you use third-party assets then you probably can't do that any more.
Just speaking from a practical perspective here... I'm working with people and want them to freely use the code that I've written and the assets I've made.
Yep, as far as I'm aware none of the larger engines UE4 or Unity mind if you release your source code under a non viral FOSS license.
But almost all third party assets have restrictions, it's not like the assets can have DRM to prevent the paid for asset being redistributed and used in other works.
For example, in a game jam you might want to be able to push something to a public Git repo that anyone can pull from and build, and license it so people on the team have no question about whether they can share the code with other people. Easy way to do that is to have an agreement like, "Let's license our code under MIT and make the art CC BY 4.0. Agreed?" Then drop copies of the license text in the repo with everyone's name on it, and make the repo public.
As soon as you use third-party assets then you probably can't do that any more.
Just speaking from a practical perspective here... I'm working with people and want them to freely use the code that I've written and the assets I've made.