I wish AWS would adopt HTTP/2 quickly (for Elastic Load Balancer). Hopefully AWS IPv6 adoption isn't any indication of how fast they'll get to HTTP/2.
On that note though, can you pump HTTP 2.0 traffic through a TCP listener? I haven't tried.
Yes, we're using that right now with Proxy Protocol to see the original requester. When using a TCP listener, you're of course free to use any TCP protocol of your choosing, including HTTP/2.
A consequence is that you have to terminate TLS at the webserver instead of at the load balancer.