Truth be told, IPv6 still doesn't work. I've stayed in plenty of hotels and plenty of airport Wi-Fi that only had IPv4 routing. Until it's universal, it can't be considered a solution.
Fortunately public facing systems are capable of being dual stacked so that won't be a problem. There's no reason internal networks can't be v6 only. Microsoft's already done it.
Back up about 20 years and you could say the same thing about the (IPv4) Internet as a whole. I stayed in plenty of hotels which had zip for connectivity back then, but here we are now.