I think "opinions about his coaching ability" is very subjective but the rest are valid points.
If we can't use subjective evidence then he should be fired today. The most subjective piece of evidence in this debate is the view that he's a good coach who needs more time. There is very little factual evidence supporting the assertion that he is an excellent coach.
Most people who work for a living are subject to opinions about their ability when they are hired, fired, promoted, or demoted.
Another thought - have we ever fired a football or basketball coach too soon? I think we've always been a year or two late. Time will tell if that's the case here.
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