Litecoin hype was died when their own Founder decided to sold his holdings long time ago when the price is on ATH.
Yep, after Charlie Lee dumped his coins into the holder, LTC is basically "dead." It might not be an instant death, and there's still a pump, but it can't rise over its previous market cap position.
Moreover, too many coins have similar purposes, only for payment, such as Bitcoin Cash, XRP, Doge, etc. So #20 on the market cap is actually good, considering how outdated the technology is.