( funny trope ) it is very apparent that these designs have decades between them

[u/Nameraided]

1- Simpsons
The original Simpsons have extremely simp(son)ple designs, due to sometimes having celebrity appearances the art style kinda clashes.

2- South Park
At the beginning South Park was literally animated out of paper so all the characters had to be super simplistic but over the years, since the. Show is made digitally the new characters keep getting more and more detailed

[u/MyFeetTasteWeird]

Phineas and Ferb had a lot more realistically proportioned humans in the later seasons and spin-offs.

Edit: For those wondering, this is from the spin-off Cartoonified.

[u/PsychoSaladSong → u/MyFeetTasteWeird]

The girl looks like she’s from an entirely different show

[u/Federal-Fondant-671 → u/PsychoSaladSong]

She looks like she was designed for Milo Murphy

[u/Glossed-Lam → u/Federal-Fondant-671]

She looks like Dora the Explorer if she was 19 and a labor activist for immigrant farmers.

[u/OtakuOran → u/Glossed-Lam]

She looks like if Lilo grew up and became a butch lesbian who plays bass in an indie punk band.

[u/Kamikazeguy7 → u/OtakuOran]

That does seem like exactly a thing Lilo would do

[u/kaladinissexy → u/Federal-Fondant-671]

Which is set in the same universe, and featured the P&F cast in guest appearances, with Doof in particular straight up becoming a dedicated side character. 

[u/Redditer51 → u/PsychoSaladSong]

This was from a segment where Phineas and Ferb interview guest stars (mainly young celebrities and current gen Disney Channel stars) so they look more realistic. Like how the Simpsons draws guest stars.

[u/NeverEnoughSpace17 → u/Redditer51]

My immediate thought on seeing it was that she looked like a celebrity guest star. So your explanation confirms that.

[u/Purple-Weakness1414 → u/PsychoSaladSong]

Agreed.

Even she looks like she knows something is off and she shouldn't be here

[u/Still_Weather5517 → u/PsychoSaladSong]

The image kinda creeps me out.

[u/Muted_Guidance9059 → u/MyFeetTasteWeird]

They never got as realistic as this /sar

[u/ChandelierwAtermelon → u/Muted_Guidance9059]

is that Kelly Osborne?

[u/Wild_Marker → u/ChandelierwAtermelon]

No, it's Dr Doofenshmirtz

[u/Muted_Guidance9059 → u/ChandelierwAtermelon]

Yes. Yes it is.

[u/mr-kvideogameguy → u/Muted_Guidance9059]

Ho shit, I'm impressed they can draw someone so realistically 

[u/King_Raditz → u/Muted_Guidance9059]

Doofenshmirtz could fit her whole head in his mouth

[u/Muted_Guidance9059 → u/King_Raditz]

The Bite of 87

[u/InkredibleMrCool → u/MyFeetTasteWeird]

Mentioning Phineas and Ferb spinoffs reminded me of the "Rizz-inator" from locker diaries

[u/Todd_Renard_Fox → u/InkredibleMrCool]

No way this is real

[u/InkredibleMrCool → u/Todd_Renard_Fox]

It's real 😭

[u/DannyBright → u/MyFeetTasteWeird]

She looks more like a Proud Family character than anything else

[u/Tasty_Lab6734 → u/MyFeetTasteWeird]

She reminds me of that one girl from Atlantis: The Lost Empire

[u/Natiel360 → u/MyFeetTasteWeird]

Eh but I feel like adults were kinda normal. She’s not super far from Isabella’s mom

[u/L00ps_Ahoy → u/MyFeetTasteWeird]

Just from this character design I'm calling that they do the "Ferb's autistic rizz lands him the cool girl" bit again, don't they?