I don’t think it’s ever okay to be cruel, insulting or mean. Or malicious, vindictive or sadistic. I just can’t go into ‘acceptance zone’ with those behaviors. Aggressive has its value in some settings and teasing is too varied. It can be fun and lighthearted, and that’s perfectly okay.
I do think that, if you accidentally hurt someone while teasing, it warrants an apology.
A fiery tongue lashing— it depends on how, along with the intent and motivation. If it’s in self-defense and intended to set boundaries, clarify expectations, etc, then I think sometimes it’s warranted, but if it’s cruel, then no it’s not necessary. Where I am coming from is sometimes people don’t give a FF what you have to say until you get angry enough to get their attention, then they finally listen. That’s not cruelty, but setting your expectations.