Other than FSU in the last BCS era title game, there hasn't been a Florida team that's done anything.
At best, you could argue both regions are on equal footing in terms of underachieving. But UF, FSU & Miami haven't done anything in the playoff era.
I'm talking about our lifetimes. The Texas teams have won 3 national titles since WW2. The Florida teams have won 11 and played in at least 17.
In the playoff era, I agree with you. Florida teams have underachieved and are trending in the wrong direction. I'd say this is one of the biggest problems:
From the past four First Rounds:
Michael Penix (Tampa) - Washington
Dallas Turner (Ft. Lauderdale)- Alabama
Quinyon Mitchell (Williston)- Toledo
Terrion Arnold (Tallahassee)- Alabama
Devon Witherspoon (Pensacola)- Illinois
Jalen Carter (Apopka)- Georgia
Calijah Kancey (Miami)- Pittsburgh
Zay Flowers (Davie)- Boston College
Evan Neal (Okeechobee)- Alabama
Pat Surtain II (Plantation)- Alabama
Mac Jones (Jacksonville)- Alabama
Alex Leatherwood (Pensacola)- Alabama
That's a lot of dudes leaving the state.