The way out is to learn more. MERN/MEAN is a flash in the pan relative to the trajectory of the industry. You have to keep learning and never stop. Yes, learning Python will help you get more jobs. But so will learning C#, or Java, or getting AWS certified, or Azure certified, or learning tensorflow, or learning perl.

Learning more things will open up more job opportunities. It always has, it always will. And your local job market is not big enough to accommodate all skills, so if you want to stay where you are, try to assess what skills are present in the job postings you want and learn those skills.

I want to college and got a comp sci degree but they didn't teach me any frameworks. I had to learn everything industry-related on my own. I share this because you do not need a school to give you a degree that says "this person knows python". But you do need to spend your free time learning more things if you expect to adapt to the constantly changing tech landscape.