Performance optimization is hard because it’s fundamentally a brute-force task, and there’s nothing you can do about it

There is, "common sense" seems to accelerate that bruteforce work. Also some developers seem to be better at performance bruteforce than others, some enjoy it, others hate it.

Simplicity also plays a very important role here, most software is built by adding more features and at some point you may be able to simplify things a lot and make run a lot faster if you just rewriting it with all the use cases in mind.