Nope.
Why would Tesla, which is paying for free bandwidth for most Teslas on the road, be paying for 5x the bandwidth when pretty obviously most folks can't even tell the difference.
Even back when the S has a dedicated setting with the higher end stereo the highest they let you go was 160kb/s and that was on a lot more expensive car than the 3.
Uh, not sure what that image is from?
The Slacker app in the car doesn't tell you the bitrate.
If you mean you changed it on the website, they doesn't do anything to the quality in your car.
Again, directly from Slacker themselves-
Audio Quality