Even if your SOCKS5 proxy supports UDP, most anti-detect browsers (in particular, Chromium-based ones) do not know how to route WebRTCtraffic through a proxy. The reason is technical limitations of the browser core.
To date, captcha systems are already introducing enhanced checks for the presence of WebRTC, as an example you can cite Discord, they have connected "Hcaptcha-enterprise", which already includes a check for the presence of an enabled WebRTC on the user.
