They Changed It, Now It Sucks: Others, particularly older fans of the original cartoon, loathe it for its ham-fisted attempts at parody, the overuse of cliché cartoon sight gags, and the entire Spin-Off Babies angle of the show.
They Are All Grown Up: Wow! Fred was a dork with a crew-cut! Shaggy was a cute kid before puberty smacked him! Scooby was a growing pup! Preteen Daphne is quite a fine wine! And how did a tiny little girl like Velma grow up and fill out...a lot?
Vindicated by History: This show was lambasted back in its day for its repetitive animation (especially seen in its dance montages), formulaic nature and for contributing to the trend of "babyfication"note making kid versions of popular '60s/'70s and earlier shows that was going on for cartoon franchises in the 1980s. Nowadays it's fondly remembered for being the first Scooby-Doo series to not take itself seriously by frequently lampshading and parodying the clichés and tropes of the original formula, paving the way for later incarnations.