Google Earth has never had historical imagery for street view like it does for aerial and satellite imagery. But Google Maps does have archived street views for some areas. Did you know you can switch directly from Google Earth view to Maps by clicking on the map icon at the top of the Google Earth viewer - it's not obvious what the icon is supposed to represent but it is the last icon on the right of the list. Mousing over it verifies its purpose.
“Science is an ongoing process. It never ends. There is no single ultimate truth to be achieved, after which all the scientists can retire.” ― Carl Sagan, Cosmos