I'm an adult who's been programming computers professionally for 20 years, and went to school for it, and I've lost most mathematical skills past what I'd learned by 6th grade or so, from lack of use.

People who aren't even working in a field that's STEM-adjacent have even less use for stuff past simple algebra and geometry (the latter mainly useful just for crafting hobbies and home-improvement projects) and a handful of finance-related concepts and formulas.

I expect to go to my grave never having found a reason to integrate something, at this rate.

The result is that any time I try to get back into math (because I feel like I should, I guess?) it's not really motivated by an actual need. The only things that don't bore me to tears for sheer lack of application ends up being recreational math problems, and even that... I mean, I'd rather just read a book or do almost anything else.

For nostalgia I keep a copy of Mathematica on my laptop, so I can pretend to be an an actual computer scientist and not just an overpaid button-presser.

Ten years ago I used it to fit a nonlinear model to some performance metrics to predict the behaviour of a disk array past the maximum load level I was allowed to use for testing.

That’s the last time I did something that Excel couldn’t handle.

In university I learned how matrix exponentiation can be used to calculate the maximum throughput of a mesh network. In real life everyone just buys 10x the bandwidth they need.

It’s depressing.

Do you play any games that require mathematical reasoning? You might realize you are using integration without calling it integration i.e. calculating expected values.