Exactly, it's not necessary. All it does is add complexity and unnecessary failure points.
Mobile providers use IPv6 for a reason. CGNAT is still used because, among other reasons, the internet (at least in the U.S. and Europe) is still predominately IPv4. If IPv4 disappeared tomorrow CGNAT (and the centralization of mobile network egress points) might be able to go away, too. If, additionally, QUIC completely replaced TCP, I can't think of any reason for maintaining such choke points.
In as much as IPv6 provides a faster, more reliable network, it benefits QUIC. And the more ubiquitous QUIC becomes the easier IPv6 will become to manage.
QUIC won't be a panacea any more than IPv6 was. But they're both important improvements to the network.
Mobile providers use IPv6 for a reason. CGNAT is still used because, among other reasons, the internet (at least in the U.S. and Europe) is still predominately IPv4. If IPv4 disappeared tomorrow CGNAT (and the centralization of mobile network egress points) might be able to go away, too. If, additionally, QUIC completely replaced TCP, I can't think of any reason for maintaining such choke points.
In as much as IPv6 provides a faster, more reliable network, it benefits QUIC. And the more ubiquitous QUIC becomes the easier IPv6 will become to manage.
QUIC won't be a panacea any more than IPv6 was. But they're both important improvements to the network.