People who are emotionally invested in matches, and don't have a complete understanding of the rule and interpretation, don't like when someone who has a better knowledge of the sport (but no emotional investment) makes tough calls. This is especially true because Angel does mostly high stakes duals and 50+% of the audience is going to be unhappy with some of the the calls.
There is a reason why he continues to get the big matches and that is because he is consistently rated as high as just about anyone in the country on his application of the rules, mechanics, positioning, etc.