For the FSU class for fall of 2023, it was a 25% admit rate with the 50th percentile at a 1310 SAT. OP’s son has a 1240 which was the 25th percentile for that entering class (source). Since it’s a Florida public school, one might assume that the university might prefer its out-of-state students to have a higher test score than its in-state students.
But then we look at what it was for the most recent incoming class, Fall of 2024. College Navigator doesn’t have this data set yet, but per FSU (source), the 25th percentile this past year for fall entry was 1360. For students accepted in the summer, the 25th percentile was 1280. Although I haven’t seen what the acceptance rate was for fall 2024, I can’t help but suspect that it’s lower than it was for fall 2023.
So yes, OP’s son has a great GPA, but FSU is not test optional. And since OP’s son’s test score is below the 25th percentile, his odds would be lower than the odds for admission to the university generally speaking, hence why I placed it in the low probability category, which is also where OP classified it.