Why are Liu Bang and Zhu Yuanzhang called beasts by many people? Why do China people show so little respect for their ancestors?

at least I don't think they are animals.

Han Xin was killed by Lv Hou. Liu Bang had a problem with Han Xin, and he was afraid of Han Xin's rebellion. He just degraded him.

As for Zhu Yuanzhang, he went a little too far, but some heroes took credit (there was a rebellion by heroes). Who wants their country to be taken away by outsiders?

swearing is just a matter for scholars, not our business.