I really dislike the assumption that good degree = good job.
I've got a first from a top university, because I'm intelligent and in my family, that's just what you do. You get top grades in school, go to university and do well. But after that, the script ends abruptly 
So after I graduated, I had no clue what I was meant to do next. I didn't know what I wanted to do, what I could do or even how I could find out. If that sounds a bit pathetic and helpless, well, yes - and I spent a long time interrogating myself about that and why I was such a failure. I've always been amazed at people who know how to navigate this stuff.
I used to wish, sometimes, there was some sort of Soviet-style job allocation scheme, where you'd take a test and be told to show up at X location at X time for work.
Add to that a weird, awkward personality (often, people say that before they got to know me, they found me aloof or standoffish - I'm not, at all), and difficulty with eye contact and conversation, and you get someone who isn't going to blaze a trail up the career ladder.
So because I needed to eat and didn't want to go home to my parents, I took jobs in cafes and shops. I didn't mind it - I liked that the tasks were clear and the work was physical and busy. I made friends and lived in shared houses and was happy enough. My best job was a glorious year abroad working in a factory. I really liked that.
Anyway, after a few years, I met DH and quickly got pregnant, and that was the perfect excuse to put the whole career (lack of) on the backburner and be doing something really worthwhile. SAHM to 2 kids took care of 10 years. After that, it was back to waitressing, until I lucked into my current job, which I LOVE. It's WFH, so no office politics to deal with, and while the pay isn't massive, it's more than enough for me. And I only got it because I wrote an excellent, persuasive cover letter and they didn't make me do an interview, for some reason.
TLDR - brains aren't everything. Even brains and a great work ethic aren't everything. I'd be good at plenty of jobs, but I probably wouldn't be able to get them because of how I come across. Sad but true. The greatest advantage is the ability to engage with people easily.