I agree: "We would like to be able to block unwanted requests on iOS with a proxy.pac file." Why, if the proxy is not available, does iOS let traffic go? Is this a bug? When will this be fixed?

https://developer.apple.com/documentation/ios-ipados-release-notes/ios-ipados-15-release-notes Support for cleartext HTTP URL schemes for Proxy Automatic Configuration (PAC) is now deprecated. Use only HTTPS URL schemes for PAC. This affects all PAC configurations, including, but not limited to, configurations set via Settings, System Preferences, profiles, and URLSession APIs such as connectionProxyDictionary and CFNetworkExecuteProxyAutoConfigurationURL(::::). If you configure a cleartext HTTP PAC URL, the system may upgrade it to HTTPS during PAC file loads. Web Proxy Auto-Discovery (WPAD) Protocol via DNS isn’t affected. Dynamic Host Configuration Protocol (DHCP) Option 252 WPAD may attempt to upgrade cleartext HTTP URLs to HTTPS during PAC file loads. (61981845)

Is there anyone?