I suppose Diana knew that was *not* dangerous to touch an AIDS patient. (She would be stupid to act in the same way during the Covid epidemic.)
Regarding George VI and Queen Mary, they were fighting about their position. When they first visited East End, they were booed at, and it was only after Buckingham Palace was bombed, they became popular. (I suppose they had a good bomb shelter.)
As for Richard III, he put all in one attack. If he had fled (like he had earlier with his brother Edward), he could have fought in another day.