I like how you and everyone below this comment seem to know exactly what my job involves. I've worked on somewhere around 200 different systems and been a/the lead developer on several dozen. I've worked in ~20 different engineering and science domains and gotten enough knowledge that engineers in the individual fields ask me questions about their domains and ask me to QC their Excel spreadsheets and calculations, having nothing to do with software development. I've worked with 6 different database technologies from FoxPro to SQL Server to Redis. I've written code professionally in 8 or 9 languages. I've written programs to calculate statistical outliers, perform mass-balance calculations, do spell/grammar checking, unit conversions, translation, some light AI, and lots more. I've written proposals and made marketing materials. I've worked with hundreds of different people on projects of all sizes.

So everyone assuming that I stopped learning anything new 12 years ago can fuck right off.

I'm not saying this to brag, I'm saying this to point out that all these assertions that "you should change jobs every 2 years or you stagnate" or "you can't learn your job deeply in 2 years" are both completely unfounded bullshit assumptions. It completely depends on what the job is.