[yummyfajitas]

If a physical trait causes people around someone to feel fear, alarm and distress, then that person actually is threatening and it's not acceptable.

As noted above, other physical traits (e.g. blackness) also cause those reactions. Your claim - namely that people's subjective perception, rather than objective behavior, are what determines the bounds of acceptability - seems to prove too much.

[DanBC]

It's not the physical traits of height or maleness or colour, but the anger displayed.

Perhaps I should have phrased it as "Don't have a work environment that regularly causes your employees to display anger"; and "Support your employees with workplace stress".

But still, anyone who is regularly angry at work needs to realise that their behaviour is not acceptable.