Exactly!
I mean, I do find it useful to check someone’s background if they provide an ID for something I know is a bit tricky or is not so common and distinctive that the average user is likely to be familiar with it.
It can help to get a sense of how reliable/well-founded the ID is likely to be and decide what I want to do next (such actions might include: consulting resources, asking the user about their ID, tagging other users for additional confirmation if something seems questionable, doing nothing and simply waiting to see what other members of the community suggest, etc.).
But someone’s expertise should not be the sole basis for agreeing with their ID. The top expert in the world may still make mistakes: because they overlooked something, because they are tired or in a hurry or distracted, because they chose the wrong item from the dropdown menu, etc. It happens to every single one of us.
I have said this before, but I think it bears repeating: while agreeing with someone’s ID may be meant to indicate appreciation and respect, there is a sense in which it often actually feels like the opposite. If I put time and effort into an ID (researching the taxon, acquiring the skills to interpret literature that is often not designed for field identification, etc.), it doesn’t feel respectful of my work if someone spends 2 seconds looking at a picture, decides that it looks good and I must know what I am talking about and clicks agree without doing even minimal research of their own – it is like copying someone’s answer to a math problem without working through and understanding the math oneself. (Again: not about gatekeeping or some idea that if I had to suffer then others must also; I would be delighted if my efforts spare someone wrong turns or make the process easier for others in the future – but taking credit for something without understanding it is not the same thing as following a map someone else has provided.)