How true is that Litecoin is not having enough developers to keep this blockchain active? One of the things litecoin has on its favor is Segwit and LN already activated, something that many other altcoins are having it only in their plans.
More than 90% of Litecoin Development historically is simply just doing Bitcoin-Core updates. Mimblewimble is pretty much one of the few ways Litecoin is trying to go its own way, but we will see.
So, IMHO, it is less about developers and more about how far, the powers that be, want to 'stray' from Bitcoin-Core vs the features/etc that Litecoin launched with and the few added tweaks up to this point in time.