if you have a Ph.D. in science/engineering and want to get a job related to your speciality, then yes, that's the case. also, it's a no-brainer since there are very few jobs (in either industry or academia) where you can be paid to work on your ultra-specialized field of expertise.

but if you want to get a well-paying job period that doesn't involve your dissertation work, then there are far more options. in fact, the best paying jobs out of Ph.D. are those that have nothing to do with your dissertation work (e.g., finance, engineering at top firms such as Google/Facebook/etc., management consulting).