I'm not certain whether Johnson is writing about himself. Johnson was a soldier and the police officer of 20 years he seems to be describing but Johnson didn't quit in 2021, he was forced to retire in 1999 due to mental health problems. If Johnson is reprinting somebody else's writing, he provides no source or authorship. If Johnson is writing about his own experience (as seems to be the case) then all the contemporary references to YouTube and Antifa seem strange because Johnson never experienced any of that as a police officer in the 90's. Johnson is a successful crime novelist and beekeeper who lives in the Welsh countryside. When Johnson talks about corrupt senior officers, bureaucracy, politicians he seems to referring to his present campaign to bring a civil lawsuit against Libyan nationals who murdered a police officer in 1984 in Johnson's presence.
If Johnson is the author, that might explain why the complaint is written as a general condemnation of everybody rather than a specific allegation of any wrongdoing. I guess we are all included when Johnson describes "the public" as violent, lying, abusive, spitting, constantly screaming for destruction of anything and everyone if they don't get their own way. If that is really any police officer's perception of the populace he is charged with protecting, that the whole of that public is violent and lying, then I would say that any relationship that officer has with any part of the public should be quickly dissolved and good riddance.