Yes, when a person wins, then he or she is the rightful owner of that title, until another champion comes along. Whatever he did, he's still the person who won the championship. Why take away his title? It should be given back to him, and other measures, if necessary, can be taken instead.
The reason that they took his title doesn’t make any sense to me. Yes, they should give him his title back and not make this person have to fight for something that he already had and had every right to have. I'm still trying to wrap my mind around their reasoning.
Yes, it is my belief that the UFC should return Conor McGregor's championship title in the UFC to him because he is well deserving of the title because of everything else that he has won, he has proved time and time again that he is the best in his league and he deserves to be recognized for that.
I'll be frank, I don't fully understand how the UFC works with its weight classes and who can fight where. It is my understanding, though, that anyone who legally qualifies in a weight class can fight in that class. Should Conor have been able to switch weight classes and immediately fight for that classes' title? I don't think that was right, but that is the agreement that was made prior to the fight and Conor won.