I totally agree that this altcoin bubble is crazy. However I can imagine having bitcoin share market dominance with Litecoin.
People are getting more and more interested into altcoins and so they have to buy it with bitcoin or ether. They probably don't like btc or ether because it is slow and expensive or clogged. And when they see that smaller exchanges where you can find those altcoins are using litecoin as a trading pair, they will like using it and might trade back to ltc. Also if a bigger exchange accepts litecoin as a trading pair it could make it take off.
Anyway not saying it will, but I know that I prefer using litecoin recently, so I'll keep a good share compared to bitcoin.