On macOS, the proxy is best effort. Programs that ignore HTTPS_PROXY/HTTP_PROXY can connect directly. This is a platform limitation (macOS Seatbelt doesn't support forced proxy routing).
BUT, the default behaviour (no net) is fully enforced at the kernel level. Domain filtering relies on the program respecting proxy env vars.
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On macOS, the proxy is best effort. Programs that ignore HTTPS_PROXY/HTTP_PROXY can connect directly. This is a platform limitation (macOS Seatbelt doesn't support forced proxy routing).
BUT, the default behaviour (no net) is fully enforced at the kernel level. Domain filtering relies on the program respecting proxy env vars.