Hmm, interesting. I tried Vultr a few months ago and had a number of issues, wonder if that was related. Is it common for a provider to only give out v6? My experiences is really only with Linode - which I've never had a problem with for years, and a bit of playing with DO which seemed fine but didn't wow me enough to move infra.
I'd be more accurate to say it's becoming common for providers that compete on price to give IPv6 a price advantage. I don't use Vultr, but they seem to occasionally have $2.50/month instances with IPv6 only. Hetzner charges you $0.50/month for an IPv4 IP for cloud instances, and $1.70/month for one for dedicated servers.
Hetzner sells v6 only dedicated servers, you have to pay a little extra for a v4 address now. So yeah, I'd consider it pretty common.
I have a weather station I run on T-Mobile which is v6only with a ipv4 CGNAT. I just Cloudflare the v6 endpoint and my legacy (v4) users can visit the station.
