Ignore those whose perceptions are pre-set. Some mechanics are great problem-solvers and smart people. Others are poor techs, lazy and crooks. The problem is that the barriers of entry to the profession are low. It isn’t hard to find work in the field, or to start your own garage. To excel takes good work in a steady environment so your reputation can develop. That takes time. I have found several mechanics I really admire. I drive more than 100 miles to take my car to one of them.
I think the problem also is that many people don’t understand automotive issues. That lack of understanding is ripe for mistrust when things don’t go well.