There are different modules for different genres. And they can be combined to combine features from those different genres, is what I gathered from it...but you would still be locked into whatever the constraints of those modules were.
For example, in the comments, it's mentioned that this won't ever support 4 directional scrolling. That means it would have to be achieved like the original Legend of Zelda. A compromise that would work fine for most games of that nature. But it would also mean a game like Mario 3 would be near impossible to pull off. If I understand it correctly anyways.
At the end of the day though, it's never the tool that makes a game good or fun. I'm sure that there will be plenty of people who put a lot of time and effort into it and make some great games with this.