I'm quite surprised that this appears to not require root - will give it a try

It creates a VPN, this is why rooting is not required. BTW, I use NetGuard with similar functionality.

Blockada is also a similar app (local vpn that filters by dns)

https://blokada.org/

NetGuard and TrackerControl (which is based on NetGuard) are comparable alternatives.

https://github.com/M66B/NetGuard

https://github.com/OxfordHCC/tracker-control-android