The following distance setting is already wildly janky and virtually meaningless with current production AP - an issue that's only recently started happening, as it used to actually adhere to its user's manual description (varies by speed). As it is now, it wildly varies based on the variation of the speed delta of traffic (yeah, decode that), which is virtually useless since Flintstone-driving traffic (people driving with their feet instead of cruise control/driver assistance) is constantly changing its speed. Net result: there is no set following distance; it just does whatever, whenever. Eats tailpipes for slowing traffic and leaves a football field when accelerating.
I would instead ask for a distance setting based on lane position - right lane: far distance, left lane: close distance. I constantly adjust my setting based on this while in traffic, but it's obvious it has nearly no effect.
I hope this improves when AP goes "single stack" soon. FSD driving (on city streets) does seem improved, at least when it's not applying "boost logic" freakish acceleration in/after turns and lane changes.