If someone in a profession is dishonest, does that mean everyone in it is the same?

No. One person deceiving others does not mean everyone in the same profession is doing so. If there is a real problem, of course you can point it out. But you need to explain what the person did and what was unreasonable so that there is something concrete to discuss.

In my early years of providing religious services, I often met people who called us frauds as soon as they heard about fortune-telling or deities. I would ask them to consider another perspective: if a police officer has committed a crime, does that make every police officer a bad person? Likewise, a problem with one teacher does not establish that every teacher in the profession is the same.

I am willing to accept opinions and corrections, and religious work can be examined too. But discussion needs to concern specific events. You cannot dismiss someone entirely with an insulting label simply because you are in a bad mood. Describing the actual behavior gives everyone a chance to distinguish what happened.

I also worried about this effect when we discussed news about soliciting religious donations. Some people take advantage of the public's respect for religion to do improper things. This can make people distrust monastics whenever they see them, depriving even those who really need help of support. Those who do religious work must be especially mindful of their words and actions and practice sincerely. They must not use other people's trust to satisfy their own greed.