As long as significant number of end user connections are IPv4 only, pretty much all services will be available on IPv4.
As long as no significant services are IPv6-only, significant numbers of ISPs and end users won't have IPv6.
It's a vicious circle. Increased adoption does not help this at all. Whether 20% or 90% of traffic is IPv6, still 100% of end users and 100% of services require IPv4 connectivity.
It's not clear how to break out of this. The complaint that IPv6 isn't compatible with IPv4 is old and easy to make but at the same time no "compatible" proposals have been made that work and address the key problems.