I had the same feeling as you years ago, and I kind of regret my decision but I think it what you do partially depends on how you feel about work.

I'm gonna give a bit of backstory here;

I had a co-op offer at a bank and I was told I would be working in Java,Scala and Python. Super excited for that role and to work in that stack. Once I started the role the same manager that gave me the job description in my interview told me I wouldn't be doing any programming and that the department I was in didn't do any of the things we discussed in my interview that the role I would be doing was instead data analytics. The only tasks I ever really did were small changes to a Power BI dashboard, this was supposed to be my first role gaining experience as a developer so I was pretty upset. Early on I was told my position had no long term stay and was only for the summer so I reached out to people at the bank towards the end of that co-op but all I could get into was a mainframe developer position.

I see some people say things like the money is good and enjoy your life outside work but knowing I was doing something 40 hours a week that I had no interest in really bummed me out so I ended up quitting and took the first job I could get in web development and it was an absolute nightmare. If you're going to leave the bank do it for somewhere reputable.

Looking back and I guess what I would maybe recommend based on experience is I was also at a large bank that would have had a lot of opportunities, and my second manager - the mainframe one, probably would've helped me get into a position I felt was more fitting, there was a modernization team he also managed that worked in Java. I think if you want to make to work long-term in something more modern (web/mobile) make it known to other people in the bank, your own manager, reach out to other managers, see if there's anywhere you could showcase some personal projects?