Science should be a dispassionate search for facts, following evidence. When feelings are interjected, or someone equates a particular theory with their ego, then that dispassionate search for answers may be seriously compromised.
It amazed other undergraduates in the Geology Department I studies at that another student and I could take different theories about the sedimentology and depositional environment of a rock formation and argue vehemently for one theory or another, pick apart one of both and then still be friends. It was because we were not married to ideas, but to finding out which (if any) withstood critical analysis. Good times, those.
Nowadays, though, with big money, prestige, and political power in the mix, truth is often a casualty.