The reason I'm cynical about it is because it starts out as you describe. My early assignments were pretty much just tailoring statements so that communications were sensible & devoid of inconsistencies. Making sure that people & organisations sent out information that was intelligible & made them look as professional as possible. Bland stuff.
Trouble is something awful happened. I got to be good at it.
When you get good at it they move you to other things. I ended up being told to draft press statements & corporate responses on behalf of a company who were the subject of legal action for multiple instances of negligence that put people's health & lives at risk. I was told to rubbish the evidence of the people making the claims, question their character, their honesty & even suggest that what happened was their own fault.
The company in question were guilty as sin in every respect. It was horrific. I couldn't stomach it. So I walked out. I also made sure that the people making the claims came into possession of some interesting information. They won their cases & I felt a bit cleaner.
The point is, the higher up the ladder you go the more it stops being just effective use of information & " spin " & becomes manipulation & out & out lies. Cynical is exactly the right word for how I feel about it. Because I can always see when it's at work. The tricks of the trade haven't changed much over the years.