I'm getting my PhD in finance and i can see the pros and cons of the process and outcomes for peers and those who have recently gone through the job market and landed positions inside and outside of academia. Academia is, of course, the #1 job market for freshly minted PhDs. The knowledge base, skills, and social training that come with the degree are just about perfectly suited for a research career in academia, but there are certainly spillovers into industry, entrepreneurship, or a variety of other areas of productive life outside of the Ivory Tower.

That said, academia is the dominant market for PhDs and that market could certainly be viewed as a bubble after decades of heavy subsidization from governments and a weird social training that funnels young people through expensive / inefficient liberal arts degree mills; the proximate cost appears cheap to super high discount rate teenagers (read: not-so-forward-thinking) because of all the government subsidies, and there has evolved a social stigma that not going to college somehow means something's wrong with you.

So overall the risk-effort-cost-reward equation for getting a PhD has certainly shifted a bit over the last couple generations. PhDs still earn, on average, higher wages, but that's likely highly sensitive to the subject area, and I don't know of any statistics that normalize for the cost input (including opportunity cost).

What I am doing myself, and what I recommend for those considering a PhD, is to seriously consider the subject area and make sure there are decent spillover skills you'll learn that are valued in industry, or some other area of society than academia. Then make sure that during your 4-6 year tenure as a student and then PhD candidate, you're learning those side skills that you can make use of if you decide not to work in academia, or just find that the market is saturated.

Overall, the decision to get a PhD is not just economic, but lifestyle and preference-based. You should LOVE the subject--weird I have to say that, but I know of far too many people getting PhDs in subjects they don't really care about, but think are prestigious--and you should enjoy research. As the OP said, the research aspect is balls deep in reading (often) boring and highly technical papers, thinking, thinking some more, trying things out, watching those things fail, thinking again, etc. It's not for everyone, but it's extremely rewarding for those who love the material and enjoy the process.