The Atlanta-Charlotte corridor is not unlike the Charlotte to Raleigh corridor.
If we’re shooting for 220mph, it would probably be much cheaper and easier to build a greenfield line that bypasses Greensboro entirely. The amount of sprawl along the I-85 crescent is extreme. Whereas, there is plenty of relatively cheap rural land available on a straight-line route from Raleigh to Charlotte. It’s also about 25 miles shorter.
Greensboro should not be ignored, however; to be clear, I see upgrading the NCRR to ~125mph and electrifying it as a higher priority for NC, but a straight line route should be in the plans as well.