If you have coding knowledge (JavaScript/HTML5), you can build a basic version in one afternoon using the Google Maps JavaScript API.

[Your Name / Lab Name — e.g., Urban Simulation Research Group]

Why isn't there a polished, commercial version of this? Terms of Service.

Google’s Terms of Service explicitly forbid using their maps data for real-time driving simulations that compete with Google Maps or alter the user’s perception of geography. Developers who have tried to monetize a 2D driving simulator Google Maps exclusive have received cease & desist letters.

Furthermore, API calls are expensive. Every time your virtual car moves 500 meters, the app requests new satellite tiles. For a 100-mile drive, that costs the developer roughly $5.00 in API fees. Most "exclusive" versions are hobby projects that last a few months before the developer's credit card maxes out.

To achieve a strictly 2D aesthetic while using Google Maps: