Its disrespect when thinking everything old is "bad," or that no younger audience can wrap their minds around the fact that there were other technical skills employed before CG.
The animation in TAS isn't bad because it's old, it's bad because it bad. It's below the standards of even 1950's Bugs Bunny cartoons. it's difficult to think of a modern example of TAS's particular animation style.. Even everyday average animation like Family Guy, and American Dad are far superior in technique and quality to TAS.
At least their faces move.
The only thing that makes TAS desirable is the voices of the original actors and the scripts. Some of the ship designs and landscapes could also find their way into a new TAS. Incidentally, a new TAS would not automatically have to be CGI, although that would be a possibility.