If you get a message like "your network preferences prevent content from loading privately" in Apple Mail and have to click "Load content directly" to load content, it is probably because of privacy settings.
This is a feature introduced in Ventura and Sonoma (and probably newer) which doesn't always work as expected.
To fix it, try this...
In Apple Mail... Go to Mail > Settings Click the Privacy tab Disable these options... Protect Mail Activity Hide IP address Block all remote content