I run a few low-traffic sites and find that the bots that visit are invariably IPv4. I do get traffic from what appears to be phones on IPv6, and a sprinkling of others. Because I have IPv6 set up on the home network here, I find that it will often access the rest of the world using IPv6 if the far end offers it.
That's the other side of the coin of course, your average punter just connects his router to the cable modem (or uses a smart cable modem that does both jobs). If that magically broadcasts the IPv6 magic on the local network then most modern devices will set up and use it and said punter will be none the wiser for it. If he's got to go into a configuration menu and tick a box somewhere then all bets are off.