If you're asking whether Shang-Chi and the Legend of the Ten Rings takes place in the main MCU timeline -- the same timeline in which Avengers: Infinity War and Avengers: Endgame were set -- the answer is yes.
The film's director, Destin Daniel Cretton, confirmed in an interview with Fandango that the film is set in the main MCU, and takes place after the Blip, which is what Soo was referring to in the dialogue you quoted.
Fandango: This is the second film in the MCU’s Phase Four. The first, Black Widow, was a prequel set between Captain America: Civil War and Avengers: Infinity War. With regards to the MCU timeline, when is Shang-Chi and the Legend of the Ten Rings set?
Destin Daniel Cretton: Shang-Chi is set in the present day in the MCU timeline.
Fandango: Okay. So, like post-Blip, present day, is where we’re at?
Destin Daniel Cretton: Yeah, yeah.
‘SHANG CHI’ DIRECTOR DESTIN DANIEL CRETTON REVEALS NEW DETAILS ABOUT MARVEL’S NEXT BIG HISTORIC ACTION MOVIE
If you're asking whether the Infinity Stones still exist at the point in the timeline in which Shang-Chi and the Legend of the Ten Rings is set, the answer is no, as Thanos used the Stones to destroy the Stones off-screen, between Avengers: Infinity War and Avengers: Endgame. The Stones still exist at earlier points in the timeline, though, as shown in Avengers: Endgame.
NATASHA ROMANONFF: Where are the Stones?
THANOS: Gone. Reduced to atoms.
BRUCE BANNER: You used them two days ago!
THANOS: I used the stones to destroy the stones.
Avengers: Endgame (2019)
I don't know if you watched the mid-credits scene in Shang-Chi and the Legend of the Ten Rings or not, but in case you didn't, Bruce Banner and Captain Marvel made a brief appearance, and Bruce's arm was shown to be in a sling as a result of the burns the Hulk sustained when he used the Infinity Gauntlet in Avengers: Endgame.
Shang-Chi and the Legend of the Ten Rings (2021)
Again, I'm not sure if you were aware of this or not, but in case you weren't, Trevor Slattery is the same character who previously appeared in Iron Man 3.
Iron Man 3 (2013)