After the darknet use cases, shitcoining was the main use case for bitcoin for a while.  BTC acted as the 'reserve currency' that all shitcoins traded against.

Without bitcoin, the shitcoins would have never took off the way they did.  They all needed something to compare themselves against, and they all where priced in BTC.

Shitcoins also provided easy targets for governments to go after (and still do).   Imagine a world where none of the shitcoins ever existed, and only Bitcoin was there grabbing government criminals' attention for the last 15 years.

I'd much rather have the gov sueing Ripple and going after multiple Ether scams than coming after us.

Shitcoins are low hanging fruit for regulators and politicians.  They are the weak members of the herd waiting to be picked off by the predators.