Obviously if the Lightning Network is not successfully implemented, the likes of coins like XRP will fill in the gap that banks need for fast cheap liquidity.
Will the lightning network be game over for the rest of the ALT coins that are borderline built on scalability?
Let me know what you guys think.
The way I tend to look at it is this:
It's relatively easy to make something for a single purpose. It's far more difficult to make something that performs multiple functions and do them all equally well.
Any altcoin can claim it has solved scalability because, chances are, they'll never have to demonstrate that in practice. The vest majority will never handle anything close to their maximum capacity. And the reason for this is acceptance. You can't (affordably) transfer value via a token that other people don't accept as payment. So along with scalability, we have to add other elements, like network effects, speed and security. This is the point where compromises start to come into play. Again, it's easy to do one of those things well, but very problematic to do them all at once.
LN can't do everything, but it can do a fair number of those things to a reasonable extent.