This issue should be resolved now. There was an issue with case-sensitivity in the headers that didn’t allow for the x-hubspot-trust-forwarded-for:true to be recognized in all circumstances.
If you have a reverse proxy setup, you can confirm this is working by using the diagnostic endpoint, then comparing the left-most IP in x-forwarded-for with something like the Google result for ‘What’s my IP’, and you should see the IP Determined location headers show your approximate location (assuming you’re not on a VPN).