The second result, https://www.rome2rio.com/s/New-York/California has no plane or car metrics but claims the distance by bus is 4733 km. Considering that the bus detours through Philly, Denver, Las Vegas, etc, the number you gave of 4.6K seems reasonable.
I did a search on DDG for "new york california distance".
The first result, https://www.distancefromto.net/distance-from-new-york-to-cal... has no "road distance", but claims the distance by plane is 2,441 miles.
The second result, https://www.rome2rio.com/s/New-York/California has no plane or car metrics but claims the distance by bus is 4733 km. Considering that the bus detours through Philly, Denver, Las Vegas, etc, the number you gave of 4.6K seems reasonable.
The third result, https://www.distance.to/California/New-york matches both numbers Neeva gave.