Thank you everyone for the replies, was not expecting to get this many so fast. If you think I'm greedy for mentioning monetization I was only using it as a way of further explaining what I meant by "actual game" and nothing more. SMBX is free to download so it should be free to play, I was just wanting to think aloud. And my question has been answered!
You can make games n the form of episodes and in 1.4 allows you to make it into a standalone file (but this encrypts the file, which doesn't really benefit anyone). And you cannot make money off of it, especially if you are greedy, as that will result in you having less money, not more.
SMBX internally uses copyrighted material and references so you're better off using a generic platformer or game engine like Unity or GameMaker.
While I am still using SMBX, it seems the solution is to move onto a different engine which I will do eventually at some point. SMBX is legal to use but only for non-profit, as it should be, but it's a shame this amazing editor is limited by its copyrighted material.
Thanks again for answering!