16 hours
I personally use dnsforge.de which is essentially a public Pi Hole with additional configuration choices for strict or porn/gambling blocking. While this one is specifically german, I think there are probably other such services or you could always host your own. (I know you said “major service” but it’s about the concept)
Last resort out of the AI bubble sadly not implemented (yet?) https://askubuntu.com/questions/928308/is-it-possible-to-use-ubuntu-without-ram-at-all