Note: I think you can safely expand your question to include all "interactive" puzzles (in fact you can probably go even broader, to include any puzzles requiring content hosted/contained elsewhere)
As cool as I think interactive puzzles would be, I believe they fall outside the scope of Puzzling (and StackExchange as a whole too).
The current consensus, for StackExchange sites generally, is that posts questions/answers should be as self-contained as possible. For example, it's frowned upon on StackOverflow to provide a link as an answer, and posters should instead summarise the content.
- It protects against link rot, where a post can become completely valueless if the thing it links to (or requires, in the case of a game) becomes inaccessible or obsolete for whatever reason
- It assists the goals of SE, in becoming a public repository of information, rather than an index
Another issue specific to interactive puzzles like mario maker, is: How do solvers post answers? By taking screenshots and drawing lines everywhere? Capturing a video and linking to youtube?
As I said, a nice idea, but just seems like an awkward (at best) fit for PSE...