Once upon a time, programmers cared about how performant their software was because they recognized that software was created for the end user.
Now even the good programmers don't give a fuck. Software development is now about burnishing one's resume and hoping for a massive payday instead of making stuff that's useful.
That was not why they cared. The6 cared because compute resources were incredibly scarce.
That changed. The following generation was still taught by those original folks, but they came up with a mythos around it.