I think the only part that hasn't been "fixed" is that it sends frames. 10Base-T is a new topology and cable with the bus virtualized in a hub. Switched Ethernet is like a different, intelligent network larping as Ethernet to naive stations. Signaling changes as you increase data rates and media now stretches from copper to fiber and the standard has retired baseband coax above 10Mbps. It's cool that they've made it work and kept it under the same "roof" of standards, so that we don't have to make so many vendor decisions or have regret building out one vendor's network and watching another one with different cabling or signaling take off with higher speeds and lower prices.