Given how wrapped the letter is in one-sided rhetoric and how full it is of sweeping, dismissive accusations such as "we all knew the mendacious reasons had nothing to do with academic standards"... how exactly do extract an "obvious" takeaway about the underlying events?

He spoke about Palestine and not getting enough condolences for his mother's death. Neither of those subjects jump out as "corruption".

Apathy and politicaly-motivated administration is corruption of a collegial environment and academic responsibilities.