Is it normal to still dream about failing finals 30 years later?

Mine was a thermodynamics final I was sure I'd blown, and it ran on a loop for close to twenty years after graduation. Same deal as you, no actual job stress around it, I was doing fine at work. The dream just kept booking me into that exam hall like a subscription nobody cancelled. Then somewhere in my mid forties it just quietly stopped. Maybe two or three a year now, and the funny part is when I get one I wake up amused instead of panicked, which is probably a sign I've made peace with it.

So yes, it fades, but the timeline is diferent for everyone and one guy's dad keeping them until retirement doesn't mean you're stuck with them. A few things seemed to help me. I noticed mine clustered during busy stretches at work, especially when I had a big design review or deadline coming up. My brain was filing real deadlines in the old exam-hall filing cabinet. When I stopped letting work spill into the last hour before bed, no email, no checking the schedule, just reading something dumb on purpose, the frequency dropped noticeably. The other thing that helped was small but weird: I gave myself an alternate ending. Once I realized mid-dream that it was the old exam dream, I'd make myself look around, notice everyone else was just as lost, and walk out. Took a few tries but it genuinely broke the loop. The panic in these dreams comes from that trapped feeling, and rehearsing an exit while awake seems to bleed into the dream. What I would not do is treat it as a sign something is wrong with your career or your head. It's just your brain running an old stress simulation on very familiar hardware. Engineers spend all day gaming out failure modes, so the dreams are basically worst-case analysis with no load case attached. If they were nightly, or bleeding into your days, sure, talk to someone. But a few times a year at 3am? That's just the brain doing maintenance. It'll taper off, and one day you'll notice you haven't had one in a year and won't even remember which exam it was.

I have to push back on the whole 'rehearse an exit while awake' trick. Tried that for months after reading similar advice somewhere and it never once worked for me. In the dream I'm fully convinced the exam is real, no part of my brain is saying 'hey this is the old one.' Knowing it's a dream while awake did nothing for me while asleep. What actually cut mine down was boring: I stopped drinking coffee after noon. Mine showed up way more when I was sleeping shallow, and shallow sleep was a caffeine thing. Might be worth checking that before assuming it's all psychological.