I think the worst thing is when folk are criticised for the way they talk, or the language they use, to be honest. It is almost like some are waiting for some phrases so they can post with joy about it. Having doubts about player signings or sales is ok in my opinion, we have done that for as long as football has been played. But it seems to me criticising for language used is a bit of a trendy modern thing that is irrelevant by fans these days. Speakman has been criticised more than most for this, although Beale ran him close for a while and Johnson before him. It is odd how we judge some folk.
Overuse of business (both general business and football specific) buzzwords is always a red flag, in my opinion. Too easy to hide behind. Usually invented to make stupid people feel clever, in my experience.
Not bothered about accents.