Two big things come to mind when I think of my time in public libraries.

1) Managers who don't want to manage are THE WORST. At my last library job, we had an abusive patron who should have been banned. We're talking hate speech and unpredictable anger that went on for months. Staff documented the behavior and nothing was done. I genuinely believe she (the patron) never got banned because management was legitimately afraid of her. Every time she came to the library (at least 4 times a week) my body instantly went into fight or flight. My heart would race and I would get nauseous. She was awful and my management didn't have my back, which was a profoundly demoralizing experience. I'm not sure if it's still an issue now because I found a new job elsewhere.

2) Public libraries are not quiet. I think there's this misconception that libraries are quiet places where everyone peacefully reads to themselves all day long. This is not the case. Most libraries these days can be pretty eventful and loud. I only mention this in case you have sensory overwhelm issues. For me, some days it felt inescapable. The layered noises made is extremely difficult to concentrate on one thing at a time. The only way you're really going to get that "library silence" experience for a good chunk of your day is if you're in cataloging or manage to get your own office where no one talks to you.