PG kindof is. Despite having a fairly confused backstory, her characterization is pretty solid. Also a single, incredibly timeless and iconic uniform.
Supergirl has a confused backstory, AND confused personality, and constantly changes her uniform.
Current Supergirl is solid. its more of a supermom personality. She's depicted as an adult, more mature. Def more of a mom, like Wonderwomen, then PG's oldersister/aunt vibe.
But OG supergirl was 100% girl next door, niece. which made no sense given her alien Kandor background. she aged from 14 yr old neice, to 18 year old teenager by the 80's.
(new 52 supergirl rebooted her to play off this more. She arrives at 18 or so, and has no idea what to make of humanity. she's alien. way more like starfire)
OG supergirl actually died in Crisis on Infinate earths famously.
then we get Matrx supergirl after Crisis reboot. kara never existed. instead, lex created an artificial supergirl matrix, who loved him.. its weird..
Then we get Linda danvers Supergirl. regular teengage girl gets the powers of matrix Supergirl, bestoyed by an Angel kara. (shes the blue miniskirt, with white midriff top one)
the Supergirl matrix gets taken away from her and itself becomes a new supergirl. (linda still has her powers for a while but eventually retires)
2004 reintroduced her again as kara zor-el. teenage refugee from Kandor to earth. iirc, this is the one that got super edgy. Angry/slutty supergirl.
after new 52 failed, she was rebooted again, to be in TV Show canon. Literally. moved in with that family, has a "sister", etc. that also has largely moved on to now be "woman of tommorrow". focusing on future stories.
