How about the fact that performance best practices vary on different hardware? CPUs have changed a lot, in that caches, speculative execution, and parallelism

How about the fact that performance best practices vary on different hardware? CPUs have changed a lot, in that caches, speculative execution, and parallelism are the way to get performance, and that was not true in the heyday of a classic Mac. I'm still in favor of porting to old platforms for various reasons. But we need to keep in mind that performance optimization is not one size fits all.