You seem to be affiliated to that clearly slopped service. Your rate of comments seems to be low enough to make it plausible that you're not just shilling, but could you at least disclose your relationship to that product whenever you mention it?
> Browser stealth has been a solved problem for some time now
That's not true. Bots can still automate the web and there's demand for products that allow it. It's harder than years ago, but not impossible.
Defenders are always in favor, but the demand for automating the web exists, so research keeps going. There are ways to hide everything, including residential proxies.
Your whole account is undisclosed marketing for this service. Fingerprinting in this manner is highly unlikely to be viable - there are too many middleboxes at the TCP layer to try and fingerprint on it.
This only works if it's a proxy instead of an IP-layer tunnel. I suppose you could go a step further and validate whether the total ping is realistic, but this could be trivially solved by putting C2 close to the res-proxy endpoint.
