Well FFVIIIi is just a badly written game and does a disservice to any of its characters, be they male or female. So I'll just do VII.

Tifa is a glaring example of sexism no doubt. I've always been annoyed by the people who never stop whining about character designs in these games. I don't care if their outfits are impractical so long as the outfit suits their personality. Show, don't tell. I should be able to gleam something about the character based solely on looking at them.

That is not true at all for Tifa which means her character design is a bad design. Advent Children did at least rectify this issue.

Aeris is weird because, if anything, she should have Tifa's design. Remember what I said about designs hinting at personalities. Tifa's look would fit Aeris and Aeris' look would fit Tifa. Tifa is a gentle, shy creature and thus a pretty dress be perfect. Aeris is a no-nonsense slum girl who isn't the slightest bit afraid to do whatever the hell she wants and when she wants.

Yuffie isn't particularly sexist apart from the fact she's there to be jailbait. She's a strong, independent girl who has a very good side quest about how she encourages her whole home town to patch up their broken spirit and honor their heritage.

As for if these games regressed, it depends. I don't think the characters actually got worse after VI. It's just that new graphics meant they could appeal to more teenage males, which these games are obviously targeted at.

Also I predict I will have to defend Yuna a lot next time.