Lord You Know Who 
TMNT is...more complicated.
Right off the bat, it was a "boys" franchise to MLP's "girls" franchise, so it never had the same stigma.
On the other hand, back in the actual 80s, the 80s show WAS beloved. But now, between all the modern incarnation that "Lauren Fausted" TMNT (the 2003 show, the 2012 show, the IDW comics), as well as Peter Laird openly voicing his dislike of the 80s show, the 80s show IS seen in a harsher light.
But it's still nowhere near as harsh as 80s MLP. Rather than the seeting hatred people have for 80s MLP, the reaction to 80s TMNT is more "as flawed and goofy as the show was, it was still a decent show, and it paved the way for everything that came before".
PS. If we are bring the 90s movies into this: the first one is beloved, the second one is like "it's good for what it was, provided you look past Vanilla Ice's cameo", and the third one is hated (and quite rightfully so, as it IS incredibly shitty).
Right off the bat, it was a "boys" franchise to MLP's "girls" franchise, so it never had the same stigma.
On the other hand, back in the actual 80s, the 80s show WAS beloved. But now, between all the modern incarnation that "Lauren Fausted" TMNT (the 2003 show, the 2012 show, the IDW comics), as well as Peter Laird openly voicing his dislike of the 80s show, the 80s show IS seen in a harsher light.
But it's still nowhere near as harsh as 80s MLP. Rather than the seeting hatred people have for 80s MLP, the reaction to 80s TMNT is more "as flawed and goofy as the show was, it was still a decent show, and it paved the way for everything that came before".
PS. If we are bring the 90s movies into this: the first one is beloved, the second one is like "it's good for what it was, provided you look past Vanilla Ice's cameo", and the third one is hated (and quite rightfully so, as it IS incredibly shitty).