Indeed. Also, in 3GPP until Release 9 there had to be two PDP contexts per device - one for IPv4 and one for IPv6, thus resulting in performance issues, and lic

Indeed. Also, in 3GPP until Release 9 there had to be two PDP contexts per device - one for IPv4 and one for IPv6, thus resulting in performance issues, and licensing costs for some vendors too. This was fixed in later releases when a new type was added, IPv4v6, which combined both stacks within a single context, but I heard this created issues with roaming if the "guest" operator network did not support this context type. But indeed just one address family is less overhead, and less work for the device. Thus, potentially better battery life.