> Disparagement means anything negative statement about someone or something. So the non-disparagement provision in your employment agreement or severance agreement applies to any and every negative statement. It does not matter if the statement is true or not, opinion or fact. If your statement makes your employer look bad, it is disparagement.
If you have signed a non-disparagement agreement, the best advice is likely "decline to say anything about the subject."
I'd definitely be arguing, via a lawyer, that "negative" is in the eye of the beholder. Employees do not benefit from layoffs, shareowners do, for example.