Yes but what kind of comparison is that: 1. How often do you need to execute 1000 GUI instances? 2. How often do you need to print "hello world"?

The right tool for the right job.

This is a discussion about computers being slow. As in a person asks a computer to do something and the human waits while the computer does it.

So python isn't the right tool for any job that involves human interaction.

Python _is_ slow, but even back in 2006 on a pentium 4 I had no problem using it with PyGame to build a smooth 60fps rtype style shooter for a coding challenge.

One just has to not do anything dumb in the render loop and it's plenty responsive.

Of course, if you're going to interactively process a 50mb csv or something... But even then pandas is faster.

That's because a Pentium 4 is way overkill for such a simple game.

Nah that's too general. A lot of website/app backends use Django or Fastapi and they work fine. Many more use PHP, also not a language famed for extreme performance.

It depends on the application. Personally I wouldn't use Python for a GUI (because I'd use JS/TS).

But who wants dozens of instances of a C GUI?

I'd be the first to complain about latency where it maters, but launching a Python program is perceptually instant (and significantly lower-latency than many nominally "faster" languages, IME).