I've been doing SQL Server seriously since April 2018 ( 8.21 years), specializing in performance and internals.
I like a good mystery. The problems that don't point anywhere obvious are the interesting ones: the weird interactions, the edge cases, the things that make you question what you thought you knew. I work from execution plans, wait stats, and Extended Events. Evidence, not guesses.
The most satisfying result is something that used to grind for hours and suddenly doesn't. Those are the cases I remember, and the ones I write about here, partly so I don't forget, partly because the next person with the same problem deserves a real explanation.
If you have something that needs untangling, reach out.