The word “toxic” is overused and lost all its meaning. No, it is not ok to be toxic in the actual meaning of the word (please look it up). What you are talking about is called “providing direct and honest feedback”. Btw, it can be done effectively without calling names and being rude in addition to it. Being rude is not effective, it brings anger and reactions which hide actual reasons behind frustration and advice/feedback is more easily forgotten or ignored as a result.