Specialization can definitely be a negative when you apply for a position where your degree doesn't apply.
As an employer, if you see someone applying for a "billing specialist" (read: fairly unspecialized) job with a masters or PhD, you instantly think: "This person is not going to be satisfied working this job, this person is going to want to get paid too much, etc"
As an employer, if you see someone applying for a "billing specialist" (read: fairly unspecialized) job with a masters or PhD, you instantly think: "This person is not going to be satisfied working this job, this person is going to want to get paid too much, etc"