I think Swiatek is slightly overrated, thanks in part to the lack of solid competition in the WTA right now. I mean, Raducanu won a slam for Pete's sake. I see Henin and even Venus being mentioned, and honestly I think both of them in their prime would handle her easily.
Yes, she looks good when everything is clicking, but she is still insanely weak mentally. You would have thought some success would calm her down, but I see no improvement in that area. She is just fortunate to be playing other players that are similarly weak mentally (Jabeur is a perfect example).
Right now her combination of movement, ballstriking, and court sense is far above anyone else in the world. She's setting a new standard for women's tennis as we speak, particularly as a mover, and only Zheng Qinwen and Coco Gauff come close to her athletically.
Maybe more than anything, I'm impressed by her ability to win tournaments without having her best stuff. She won this year's US Open playing what I'd consider her B- game. Being able to "win ugly" against slam-contending players at the business end of big tournaments is an ability that very few players in the history of tennis possess, and I believe Swiatek has it.
Athletically, there are plenty of others that are just as good, if not better. Giorgi, Sakkari, Sabalenka, Collins, Cornet, Putintseva, Kostyuk... They don't have the same game that she does (most days), but just athletically they are equal or better.
As for winning without her best stuff, that's because she hasn't faced anyone with their own best stuff. There is a dearth of consistent top talent in the WTA right now, and she is taking advantage of it. As I said above, if she were playing a few years ago against players like Venus, forget it. And I won't even mention the greats like Graff and Navratilova that would just school her.