How to translate this phrase?
'I have witnessed nothing but profound mediocrity'
or can you please explain the meaning of it?
Thanks a lot!

Question

Answer

It means "I have found/experienced/acknowledged nothing else other than average of something", as in "there was no outstanding element", "nothing special".

Answer

Think about visiting a government office. There is no one or anything there that is exceptional. Everyone is average or below average.  That is the mediocrity everywhere that he is talking about. "Profound" is an uncommon word and it's being used for artistic writing effect.

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