How can I delete all the Apple Watch applications that I don't use?
I only use three or four Apple applications on my watch. How can I get rid of the useless icon clutter?
Apple Watch Series 4
Here is a different link from the related article link, which lists which of the built in apps you can remove. If one you want to remove isn't on the list of apps you can remove, then you simply cannot remove it.
Click here --> Delete built-in Apple apps from your iPhone, iPad, or Apple Watch - Apple Support