In a perfect world, you do both. Both have a lot of value.
The key to both is that you want to create a network and make connections. These connections are critical to finding jobs. In the world of acting, jobs are often found because you know someone. I got more auditions when I got to know a casting director really well. It's "who you know" in this industry.
If you only can do one option, I would pick a degree because this will allow you to find more job opportunities in the future. Acting skills work in a variety of careers. And having the degree will give you even more opportunities.
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