the one reason i use pihole is to block ads network-wide. this kinda defeats that purpose.
For use on a desktop in a network you do not control (e.g. many devs have complete local control over their own machine)
I VPN to my home (and by extension my Pi-hole server) when on that kind of network. A local ad-blocker doesn't prevent MITM or malicious DNS servers. Maza won't help if DHCP is handing out the IP for a server that claims google.com is a CNAME to hereisyourvirus.xyz or if the router is transparently redirecting DNS traffic so you don't even know what DNS server you are hitting. Which means you have to use DoH or DoT as well.