I was a Java programmer out of school. My first specialization became performance. It’s the same problem with JavaScript. There’s at least an order of magnitude speed difference between using your head and just vomiting code, and probably more like a factor of forty. Then use some of the time you saved to do deep work to hit an even two orders of magnitude and it can be fast. If you’re not an idiot that is.

bcantril has an anecdote about porting some code to rust and it was way faster than he expected. After digging he found it was using btrees under the hood, which was a big part of the boost. B-trees being a giant pain in the ass to write in the donor language but a solved problem in Rust. It’s a bit like that. You move the effort around and it evens out.