Re: Google are crafty
Google will counter that by using DNS over HTTPS (RFC8484) or DNS over TLS (RFC7858) instead.
Which I counter by not running their programs and running my own DNS server and shitcanning suspect IP at the firewall level.
IP6 could be an issue. But I think I'll just make sure my guest network is IP4 only, or I do't have a guest network - if you want Wifi at my home you do it my way or not at all.