Firstly, 60 kHz is less than 75 kHz, and that is shown as 60 kHz < 75 kHz.
The minimum roll-off frequency is quoted as being 75 kHz, at -3 dB. That means that for a fixed input level, the output power will fall to half as the signal frequency increases to some frequency beyond 75 kHz. Although it doesn't say how consistent the output level is, I strongly suspect that the gain will be nearly flat until the gain rolls off at high frequency.
I would a expect to see a small reduction in gain starting at about 50 kHz, because the gain can be a lot less, about 14, by 75 kHz.