My dream has always been a toggle that switches between traditional loud sportscar exhaust and something on par with a stock BMW exhaust. Last time I checked physical switches still had a tendency to leak. The battery method could be the answer to an on-demand lower profile option.
This is super common, but the sound changes are less dependent in the exhaust and more dependent on the tuning.
In the simplest case there are exhaust cutouts that reroute the flow from a button push. Mercedes aftermarket mods are common here. But, there are also tuning changes that can be triggered in the ECU or timing changes in the valves, turbos, and other parts of the combustion flow with digital or analog input.
For instance, current EU emissions requirements keep a Ferrari F8 much quieter at idle than a 458 or 488 but it still can make the fun car sound at full throttle or with aftermarket modifications.
Look into the car you like to drive, there are many mods available, YMMV.
