why are insult and trust not counted in abstract nouns

Abstract noun refers to concepts, idea, emotion, etc. some common abstarct noun- success, depression, anger, courage, creativity, etc. Now, coming to the question- Insult and trust are not noun beacause it is not follow above point. Insult and trust are not related to emotion, that's why insult and trust are not noun. For your information- Insult, Trust, Team are not a noun.

Insult is not used as a noun here. Don't insult me = Do not insult me. If it were a noun, you could have asked here "Can I have it?" and the answer should have been - yes. But, that's not it. You get no as an answer. So it's not a noun. But, if you had asked, "Can you do it?" You get yes. So it's a verb. The same goes for trust. I can't trust her. Ask "Can I have it?" No, you can't. So, not a noun here. Now ask "Can I do it?" You get yes. So it's a verb. I hope this cleared your doubts.