This has happened before but that's not how it always works. LTC might me one of the most reputable altcoins but it has been pointed out before that it's hard for it to compete with all those next gen ones. I don't see it dying at any time, but I believe other coins would have a greater benefit from a bitcoin uptrend.
I'll take litecoin's market cap, liquidity, name recognition, and availability on multiple exchanges over any alt coin, regardless of its bells and whistles, EVERY DAY OF THE WEEK (and twice on Sundays). From a business/market perspective, these traits are a thousand times more important than the latest "innovation" of the day.