You already know me, just not under this username! I try not to put my name directly out on forums like this, but I run https://approximated.app and those 100k+ domains aren't all in one cluster, though some clusters are growing quickly and might be there in a few months. Customers paying for the clusters are generally SAAS or hosting related so they can bring a lot of user domains when they come on board and tend to grow steadily.

Ah, that's you! Thanks so much for sponsoring. Hit me up if you ever need something or would like something more/special from your sponsorship.