It's easier for me to replicate this functionality myself. I run unbound with a domain name blacklist. Same functionality, no need for additional hardware.
One of the great things about using unbound is how easy it is to blacklist entire domains, without having to know the name of each subdomain ahead of time. I've been doing what pihole does for over ten years using pfSense. I'm up to 437,000 fully qualified domain names blocked, and over ten thousand domains blocked outright. It has been years since I've seen an ad.