When I was a kid, I wanted to be a truck driver when I grew up. My dad, who had been a truck driver ever since he was old enough to do it, always told me "Don't do it, because once you're in a truck, you'll never get out of it."
That never made sense to me. If you don't want to drive a truck anymore, then just find another job doing something different?
Now, I kind of understand what he meant by that, but the problem with it is that can pertain to any career. My mother was a waitress when she met my father, and she was a waitress way before that as well. She managed to get out of food service for a few years, but now, she's right back in it as a cafeteria cook at a high school.
You work in IT? Well you're probably going to be in IT until you retire. You're a miner? You'll probably always be a miner. Factory worker? Same thing. Humans are creatures of familiarity. We tend to prefer to stick to what we know. Learning new skills is difficult, and people don't like to do things that are difficult.
I've worked in casino IT since 2019. It's been 4 years. It's a solid job with a number of required skills that are great to have, even outside of work.
Before that, however, I delivered water and coffee to office buildings and whatnot, and I've been wanting to get back into a van or a truck doing similar work. I don't think it's really a familiarity thing, though. I'm perfectly happy doing what I'm doing, and I know what I'm doing. I've just been getting kind of tired of being cooped up inside at the office all day long, only to go home and be cooped up inside at home. Maybe if I could get a field technician job I'd be happier with the job. I don't know.
I'm in the process of moving again, and I'm hoping I can land a more mobile job when I get back, but we'll see what happens.
Anyways, the moral of the story is this: If you're not happy at your job, leave and find something else. If you're not happy with your line of work, maybe try something new and see how you like it. Don't be afraid to explore the unfamiliar, you might just find more happiness there.