It has stopped, though. Single-threaded performance, either in absolute value, or per dollar has not been following Moore's law for more than a decade.

And outside of data centers, single-thread performance is still king.

Performance per watt has improved, but that's not a metric the typical end user cares much about.

Single-thread performance is not king though. Software nowadays is extensively multi-threaded. If you're still writing single threaded code for a desktop program people are going to look at you like you have antenna growing out of your head.

And performance per watt absolutely is important. People care a lot about battery life of their laptops and phones and that's strongly dependent on performance per watt.

Performance per watt is key for all portable devices, ie the laptops and phones that many do almost all of their end-user computing on.