What's the problem with an IPv6 reverse proxy? If the Internet-exposed endpoint is IPv6, then from my point-of-view of a client, it's effectively that. For what

What's the problem with an IPv6 reverse proxy? If the Internet-exposed endpoint is IPv6, then from my point-of-view of a client, it's effectively that. For what I care about, they could be running fax machines over an analog phone line beneath that point.