Using the Internet without IPv4 connectivity

I run my own tailnet (headscale as the coordinator server). Tailscale stack is essentially built on top of wireguard.

I have an exit node setup with dual stack IPv4/IPv6 addresses. So in theory if my ISPs CG-NAT failed or IPv4 was inaccessible, then configuring my device to use my exit node to reroute traffic _should_ work without having to mess with WG internals like the author in this article.

I suppose there are some caveats here since I have discovered many services do tend to flag IPs originating from VPS ASNs as "spammy" (ie, pretty much any service front loaded by CloudFlare). Maybe Hetzner is better in this aspect?

CloudFlare and friends use a multitude of factors, AS being only one of them. I am a TekSavvy customer (Canada's largest independent, i.e. not owned by one of the incumbents, ISP). Pretty clearly an eyeball network, and I get the CloudFlare captcha multiple times per day on different sites. I'm guessing it may have to do with the fact that I use custom reverse DNS entries (instead of their default schema of 127.0.0.1.dsl.teksavvy.com) for my internet facing IPv4 and IPv6 subnet.