We're about a decade further in the adoption of Wifi from when WPA2 was released. It's a completely different ballpark now that wifi is considered part of the basic infrastructure everywhere and baked in to exponentially more devices.
It took several years for people to pitch their old dell laptops and nintendo consoles that couldn't support the then-new standards. People aren't going to replace their thermostats, baby-monitors, security systems, home entertainment systems, and juicers over night.
I mean, yeah? How's that different from every other time there's a new standard?