The implication here is that the proxy fridge forwards the Anubis challenge to a dedicated rig controlled by the scraper who efficiently solves it and returns the answer.

That's still a notable step up in completely and resource investment for the crawler

See also how captchas continued being effective for years despite services like anti-captcha offering to solve them for you for a fifth of a cent each by farming the work out to India. It took advances in AI that made it viable to reliably solve them on-device to bring the end of the captcha