There's apparently a config setting to turn all animations off, though I haven't tried it myself.

The author linked their config file from the article, and it includes this:

    // Animation settings.
    animations {
        // Uncomment to turn off all animations.
        // off

I think it's boilerplate from the default config file, which would imply that the video they showed is not the 'animations off' version, if that's not already clear from the presence of animations.

You can entirely turn off all animations. You can also turn off only some, like workspace switching, and reduce the durations globally.