Rockets landing was never considered impossible, NASA even built and tested several such vehicles long ago. What was determined is that is is not economically viable which even SpaceX has started to realize on some launches where they ditch the landing in order to be able to carry more payload.

The launch pad at Cape Canaveral may not be exactly what Starship needs but it would be a good start. Like flame trenches and placing the fuel storage tanks far enough away from the launch pad.