Now with IPv6, we give each continent /12s and then each continent's RIR gives those out as /32s or /48s to ISPs, who then either pass on the /48s to their customers, or further subdivide them into /64s.
So in a way, we actually are kinda doing this /8 /8 /8 division now, but with blocks many, many times bigger, and then each subnet is 72 quadrillion times bigger, with the ability to have up to 18 quintillion devices.