You can have ip over time multiplexing data link layer, like the IP over ATM. I believe they were still used in the core voice networking. IP won because they

You can have ip over time multiplexing data link layer, like the IP over ATM. I believe they were still used in the core voice networking. IP won because they are more flexible, and open. And the Internet cement the win because of that. That's way planning ahead too far works less and less successful for bigger and bigger project. Too much dynamic is embed in the long wiring process. It becomes impossible to have a plan work out correctly.