Of course, we all have our faves and we feel a certain way when our favorite princesses are getting criticized. For me, I do feel like Tiana gets quite a bit of flack, some deserved but some is quite overboard. For example, people call Tiana mean and even ruthless for simply doing what Ray tells her by leaving him to fight off the shadows by himself but if she went against his orders, you know that would be yet another opportunity for people to call her condescending. So I'm just gonna counter some complaints against Tiana.

Human Tiana is more likable than frog Tiana.
Not really gonna disagree with that one lol.

Tiana is rude and condescending.
She's only ever rude to Naveen and Ray that one time. She has every right to be mad at Naveen, it's understandable to be aggressive towards someone who puts you in a dangerous situation. Also, Naveen is just as arrogant and judgmental towards Tiana as she is to him, just because you agree with Naveen's philosophy more, it doesn't make him anymore right or less rude. As for that ONE time with Ray that people love to bring up, she was speaking out of hurt, Ray himself acknowledges that.

Otherwise, she's pretty well mannered and respectful, she's far less prone to emotional outbursts compared to other princesses, and she takes criticism (her mom, her friends) and even flat-out disrespect (the chef at Duke's, Mr. and Mr. Finner) in stride. A lot of other princesses would either react like an aggressive brat (Jasmine) or an emotional wreck (Mulan) if they encountered the amount of dissent Tiana has to endure. She even calls Mama Odie "ma'am". Tiana may not agree with Lottie's ideals but Tiana never talks down to Lottie and she even gives her advice on how to achieve her dreams of romance. Granted most of these are when she's human, so this kinda adds to the first point.

Her character is "anti-wishing" and "anti-fairytale"
I do think aspects of Tiana's character panders to the anti-Disney crowd. I mean, it's no surprise that the first black princess just has to be a "hard-working independent aspiring businesswoman blah blah blah", but here's the thing, the reason why PATF doesn't piss Disney fans off as much as other revival films, is that it ultimately embraces the trope it's criticizing. Brave and Frozen do this to an extent as well but PATF is just....better at it.

This common argument would make a lot more sense if Tiana was a lazy slacker and everyone was nagging her to start working hard but she's portrayed as in the wrong for working too hard, her lesson is to learn to do so less and in the end while hard work helped her get part of the way, love, luck, and faith are what helped her reach the finish line. This is in contrast to Naveen who's portrayed as in the wrong for having too much fun and he learns his lesson accordingly. Are they the most well-written character arcs? Not really. Did the writers actually try to have a fair objective view on the subject from both sides? Yes.

Tiana being a frog for most of the movie is problematic and even "racist".
This is really stupid. This was just Disney trying to put their own on the original fairytale. Like "let's turn the princess into a frog too in our version! So original!" Is it stupid? Depends on who you ask. Is it racist? Hell no.

So there you go, I plan on doing this for other princesses in the future. Thanks for reading.