If the LM324 is powered from the 7.5 volt supply (not confirmed yet) the maximum typical output voltage could be at 6 volts but, it could be a shade higher (worst case) so maybe 6.5 volts. The volt-drop through the emitter follower might be 0.6 volts so, worst case (with some hand-waving) is that the LED and series resistor receive 5.9 volts.
Given that the LED might drop 3.3 volts when fed with 20 mA, the voltage remaining across the resistor is 2.6 volts and this implies a current of 21.5 mA so, immediately I can see how the current in the LED might be a little more than 20 mA.
However, the absolute maximum rating for the LED says 30 mA and, this should be OK for what I've calculated but...
If the LM324 is a different op-amp or, the LM324 positive power rail is greater than 7.5 volts, I'd begin to have stronger concerns.
Of course you can't immediately rule-out a bad batch of LEDs from the proper supplier or, even fake parts from a dodgy supplier.