scenario 2 : bitcoin goes to hell and nem is the crypto savior alternative
scenario 3 : bankster coins like ripple or ethereum swallow everything
scenario 4 : general crypto failure as a concept
u pick one
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
3 is the one we have to watch out for.
Ripple can't swallow everthing as Ripple is currency agnostic. You can use Ripple to trade any currency. It's merely a system that happens to have a built-in crypto currency as anti spam meassure. If every bank would be using Ripple it'd be very easy to get NEM into every bank as we could simply use Ripple to do that.
The problem with Ripple is that if you really get into it it's a really complicated thing to use and it's very easy to be screwed without doing anything (like literally not doing anything).