Of course it can and it can’t.
0 dBFS is the loudest signal you can play.
It is impossible to play louder than this level.
What happens if you have a recording already a bit close to 0 dBFS and you open the equalizer and add a bass boost.)?
Due to this boost the signal will exceed 0 dBFS but as this is impossible it is clipped and this you will hear as distortion.
By design the moment you apply any kind of DSP (EQ, volume control, etc) the audio is no longer bit perfect.