@SolSoCoG you are referring to IP anonymization through Nginx, right? We haven't noticed any issue since we did the change, but I think 127.0.0.1 is excluded from mastodon's rate limit policies.
In the meantime though there was a new env variable introduced for IP retention. So this custom configuration may not needed anymore.
https://docs.joinmastodon.org/admin/config/#ip_retention_period