I presume you are talking about a new saw or relatively new saw under
warranty that has not been abused somehow.
A new saw out of flat by 0.021" is unacceptably out of tolerance,
especially on a cabinet saw.
Recently, in connection with a saw problem I just got resolved, a Jet
tech told me that Jet's tolerance on a table saw top was 0.015".
I recently had Jet replace a complete Jet contractor saw body due to
the top being out of flat by 0.03". My saw was near the end of the 2
year warranty window, no hassle, no nattering questions asked.
Returned the defective saw, motor, legs etc to the retailer and took
delivery of the new saw. (Kudos to Jet!)
The table top on a cabinet saw is very easy to replace. Insist on a
Do not mess around with a table top that is 0.021" out of flat - it
ain't gonna get better with age.