Recently bought nest wifi (new version of google mesh). Internet speed is awesome throughout the home. But I lost many of the parental controls I had in my previous router. I used to be able to block certain sites, not just adult content, but also some social media sites like twitter. Now I do not see any such option in Google Home App.
It seem to be an option that was available in Google Wifi (older), but is not available in Nest Wifi (newer)? Seems backwards to me.
I have been using Google WiFi since it was introduced, and I don't recall it ever having the ability to block a specific web site. In any case, the way modern browsers have changed recently, this kind of thing is increasingly difficult to do effectively at the network level anyway. You may have more luck using the parental controls built in to the operating system of the client devices you are interested in controlling. Microsoft "Family" and Apple "Screen Time" should both support this kind of thing, and should be more effective.