Honestly gonna be blunt.
Heard her live and she's pretty decent - the problem is that the bar for concert pianists, esp touring concert pianists is incredibly high. Off the scale high. I'd say worse than violin. The level that people like Yuja Wang and Yuchan Lim have to play at day in and day out is insane. Some of these people play things like Rachmaninoff 3 5 times a week for a live audience almost perfectly. Or Prokofiev 3, etc.
I mean I just heard a BLIND guy play Rachmaninoff 3... flawlessly. Live. I've heard Yuja Wang a few times live. Entire recitals with up to 9 encores.
Tiffany's recital rep when I listened to her had some hard stuff but a fair bit of stuff that wasn't super technical. But she was pretty expressive. I'll give her that. I wasn't a fan of immediately jumping from one piece to the next and it felt like she just wanted to move on instead of acknowledging her audience.
She has the technical chops if she pushed herself harder. But, she is probably comfortable with where she is now and what she's doing and to make the big bucks the stress is unbelievable. Yuja and Lang Lang are 7 figure concert piansts. Yuja has the reputation of being a diva but the stress has just been getting to her.
The thing is to solo with the top orchestras of the world as a concert pianist is EXCEEDINGLY difficult, and hell, I'm not a pianist but I've solo'd as a classical musician in front of 2,500 people ONCE and that was enough for me. I can't imagine doing that 200+ times a year.
As it stands she could probably stay in NYC or go around Europe and just do gigs and teach lessons the rest of her life and teach at a university and get a doctorate and be just fine. I've heard a few professors play worse than she does at least.
Oh and she looks great for her age. Probably b/c she stays indoors so much and doesn't overeat. Yuja looks amazing too but she tans too much. I have a feeling Tiffany is someone who does nothing but read books and play piano all day and is likely still a virgin. I know the classical musician type who does nothing but practice and never dates.