Would you like to be treated by a surgeon who doesn't get along well with the nurses and the other staff that's in the operating room? And because of this the performance of the whole team is impacted?
Faculty, in general, don’t operate as a team like in a more traditional business. One or two or five might collaborate on a project but they typically operate very independently of one another.
Words like “collegiality” are frequently used in the academic hiring and promotion process to speak to issues that are seen as outside or parallel to merit. The problem being that the historical evidence shows that concerns about collegiality have frequently been used to disrupt actual evaluation of meritocracy in ways that specifically harm URM faculty.
Collegiality gets used because there is no real expectation that faculty act like a team, just that they aren’t active assholes to do heir peers in committee meetings.
Being difficult to work with is not a generalized negative in academia. It only is seen as a problem when someone has some other problem with you. Many faculty, in my experience/opinion, who are fantastic researchers have the emotional maturity of small children. There is a trend against that but it is far from disqualifying.
Academia, like many things, is a meritocracy until it’s not.