I know you think your home is the best, which os obviously why you chose it, but it is not necessarily helpful to have the seller there if the buyer doesn’t like your taste in wall color, which leads to a confrontation about your tastes. In reality, the buyer may well still buy the home and change the wall color later, but not if they get upset with you for berating their tastes.
The idea of showing homes is to find the one the buyer can imagine themselves living in. They want to picture their furniture, their family if they have one, their parties, and their life in the home. It is more difficult to do that if they have the image of the old seller in the home before they have a chance to picture themselves in it.
I know this is shocking, but people don’t always like each other. But, even so, this person may be the one who is willing to pay the most for your home. We are here to find a buyer who is going to pay the most for your home, regardless of your personal feelings of the person. We can avoid potential pitfalls in this way by simply never meeting them until closing and/or never at all.