Regarding WebBotauth, I've just skimmed the doc but I don't understand why didn't they have used TLS client certificate instead of this new header? Is it becaus

Regarding WebBotauth, I've just skimmed the doc but I don't understand why didn't they have used TLS client certificate instead of this new header? Is it because it's then easier for Cloudflare to strip that header than to do TLS termination?