given that knowledge of local streets is necessary to find a route there, what would be a better system?

The city I live uses a sum of two numbers given by the house position in the two directions (one on the hundreds, other on the unities) into a coarse grid.

There are plenty of cities that have numbered streets, in order.

Some cities have named "mega-blocks" as a third grouping element beyond the street/number and finer grained than the usual neighborhood name, so you have to memorize less stuff.

In short, there are plenty of schemes that give way better result. If you have to look up on a street-name database to find an address, there is little to gain compared with a house-number database.

Ok, that makes sense. When your streets are lain out in a grid, everything is easier. But most municipal road systems are far less tractable. I can't imagine easily navigating my hometown, or any other town in New England based on grid coordinates.