TLS fingerprinting is not sufficient to stop residential proxies, the proxy acts as a transparent pass-through at the TLS layer making it trivial to use something like curl_cffi to mimic a real browser TLS fingerprint.
However residential proxies do have a weakness, since they need to maintain 2 separate TCP conenctions you can exploit RTT differences between layers 3 and 7 to detect if the connection to your server is being terminated somewhere along the path. Solutions exist that can reliably detect and block residential proxies, for example: https://layer3intel.com/tripwire
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TLS fingerprinting is not sufficient to stop residential proxies, the proxy acts as a transparent pass-through at the TLS layer making it trivial to use something like curl_cffi to mimic a real browser TLS fingerprint.
However residential proxies do have a weakness, since they need to maintain 2 separate TCP conenctions you can exploit RTT differences between layers 3 and 7 to detect if the connection to your server is being terminated somewhere along the path. Solutions exist that can reliably detect and block residential proxies, for example: https://layer3intel.com/tripwire