> A new house bought today could have 10 phone sockets and 0 Ethernet sockets.

Really? I've never seen that many in a house. Most might have one extension in a bedroom upstairs. Which is usually the one room where you don't want a data connection. Crazy to think when I was little it was common to have a phone downstairs and another upstairs in the master bedroom. Who the hell wants to make a phone call from bed?!

I think it's easier just to run cables, tbh. If you can't put them in the walls/floors then hide them in plastic conduit. You can do a pretty good job with a bit of planning.