As other users have mentioned, the lightning network isn't ready for large-scale implementation, despite the fact that it has been in development for a number of years by now. Once it does get completed and can work effectively, then we can argue about whether Litecoin and Dash have any place in the crypto marketplace. Until they, they still serve their own purpose. I personally don't think that either Litecoin or Dash would become "obsolete" since many other cryptos would be tossed out due to their obsolescence first.

I'm trying to remember when they started to work on the Lightning network, it was probably at least conceptualized 5 years ago if they weren't actively working on it.