You know, I recently went through a period of thinking my MacBook was just broken. It had the janks. Everything on the browser was just slower than you're used to. After a week or two of pulling my hair, I figured it out. The newly-configured computer was using the DHCP-assigned DNS instead of Google DNS. Switched it, and it made a massive difference.
but that's the opposite of the request to move from a googDNS to a local one because of latency. so your ISP's DNS sucked, which is a broad statement, and is part of the why services like 1.1.1.1 or 8.8.8.8 exist. you didn't make the change of DNS because you were picking one based on nearest location.
There is more to latency than distance. Server response time is also important. In my case, the problem was that the DNS forwarder in the local wifi access point/router was very slow, even though the ICMP latency from my laptop to that device is obviously low.
which is well and fine, but my original comment was that moving to a closer DNS isn't worth it just for being closer especially when it is usually your ISP's server. so now, you're confirming that just moving closer isn't the solve, so it just reassures that not using the closest DNS is just fine.