Don't see any real disadvantages at all.
Life is complex.
I started wanting to be a writer, but found that I loved geology and majored in this in college and in graduate school. It was in graduate school that marine biology took over as my primary interest. I heard that it is hard to get a job as a Marine Biologist because of the few job openings. I was lucky as jobs were relatively accessible in the early 1970s but one should not enter a field without a realistic understanding of the job market. I have had 14 students get Ph.D.s and all are employed or on the way.