If they ever adopt what is in that table, current cables with 6 AWG conductors and 10 AWG EGC's would have to be made with 8 AWG EGC's. Then we are possibly stuck with needing to change out anything existing that had 10 AWG in some situations.
Might be other larger cables with similar issues.
You bring up a good point- I noticed that as well.
In Canada #6 is typically accompanied with number 8 if my interpretation of their code is correct.
Being honest (I know I'll get roasted for this) I personally have always felt that some EGCs were undersized like #6 for a 200 amp OCPD.