I'm not sure about your other points but image search thumbnails have been found by the courts to be fair use. https://www.eff.org/cases/kelly-v-arriba-soft htt

I'm not sure about your other points but image search thumbnails have been found by the courts to be fair use. https://www.eff.org/cases/kelly-v-arriba-soft https://www.eff.org/cases/kelly-v-arriba-soft