Do you have some evidence that OpenStreetMaps had a user experience similar to Google Maps in 2004? My recollection is it did not. It was like at best like mapquest. Click an arrow on the edge of the map, wait for the page to reload.

There were several maps before Google Maps but they didn't provide the smooth experience that Google Maps provides. Just like there were 100s of PDAs before iPhone but they didn't provide the smooth experience of iPhone.