Not is a pretty long time. Monarchos was the closest, and I think he was in 2001.
I do think the Derby time is gettable.. probably the Preakness too, which a specialist kind of horse. Never the Belmont... ever
The Belmont might not, esp. since that distance is hardly run anyway and they won’t generally train for it.
The others definitely possible. Monarchos’ Derby was sub-2:00, and actually 3 other horses ran the Derby within a second of Sec, including the solid Decidedly in 1962, and the great Northern Dancer 2 years later who was known for hitting the 2:00 mark.
Sec’s mark on Preakness was adjusted,so it could be questionable, but, as it is many horses have been within a second of that, including this filly in 2020 (the year I didnt watch AT ALL since the jockeys and track owners were kneeling for these riots so I don’t recall any of this) very close.