Why not? It's effective and easy to do and while it can be circumvented it will stop some players with very little effort. Also, the article is about 2017/2018.
If only I had a dollar for every time I was blocked somewhere just because somebody else had used the IP just before me to do bad stuff. Worst offenders out there never clear the list, even. In a world of a shortage of IPv4 that approach is just madness.
It's also the opposite of effective. More like bogus effectiveness. Only hurts innocent bystanders.