And then there's also TLS fingerprinting. Different browsers use TLS in slightly different ways, send data in a slightly different order, have a different set

And then there's also TLS fingerprinting. Different browsers use TLS in slightly different ways, send data in a slightly different order, have a different set of supported extensions / algorithms etc. If your user agent says Safari 18, but your TLS fingerprint looks like Curl and not Safari, sophisticated services will immediately detect that something isn't right.