Not really, some cartoons survive the test of time and are re-watchable now. Transformers is one of them, Voltron on the other hand is not (well, unless you are really, really drunk). Just because the cartoon came out in our childhood doesn't mean it would still be loved if watched now. Same thing goes with cartoons out currently, very few will be even remotely watchable 20 years from now.
For example, of the saturday cartoons from 20 years ago, which ones would be watchable now? Dungeon and Dragons (yes) or Bionic Six (hell no). Both were loved when they first aired, but D&D could be aired now and would get a loyal viewership.
Degrees of quality exist in cartoons, and those marks are exemplified 20 years down the road.
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