Your example of having engineering degrees but spending much of your working life writing is a good example of how income and academic degree don't necessarily go together. If you get training rather than an education you have a clear path but if the job you trained for is not hiring when you need a job you can be SOL.
Basically no one has cared what degrees or certifications I have in decades.
(The one caveat is the fact that I went to the same school as the ultimate hiring manager probably didn't hurt. But the decision had probably already been made at a higher level.)
The problem for people starting in the world of work in the USA is that its very hard to get a job that pays real money without degrees, certifications, and contacts. Its also much easier for most people to do the 'looks good feels good' thing if you know you have been successful and well paid in job X, and job Y would be similar. So once you are established in an industry your experience and self-acquired skills matter more than your degree, but getting in to that industry is hard And the housing shortage in most rich countries makes it hard to spend 5 or 10 years trying different things until you establish yourself in an industry that works for you.
Sure. People who have no signals (including contacts and credentials) have trouble lining up jobs other than (and maybe including) fast food. People need signals for professional work which include degrees and various sorts of credentials. I'm not sure it's much different anywhere else in the world.
Interests change too. I had degrees in Mech E and material science and I drifted into computer hardware related product management in relatively early days. From there to being a tech industry analyst and from there to doing a fair bit of early-on cloud strategy and content marketing work. Back to doing sort of part-time analyst work.
I suspect a lot of people here have had more linear and well-defined paths as the industry has matured.
I don't consider any of it a waste and I've enjoyed a lot of it. I've had conversations with people I've known for decades about it and they're kind of meh. You've done fine whether or not your formal training was necessarily on target for what you ultimately did.
I'll also add that working on newspapers has been probably been more useful than a lot of the technical stuff I've done.
