It is like asking why so many graphics engines get written, instead of using raw OpenGL/Vulkan calls and extension spaghetti all over the place.
The absolute vast majority of new frameworks don't use web components as the foundation.
Perhaps instead of burying their heads in the sand people pushing web components would should finally start asking why?
I only need to ask why, when I have to deal with React based stuff.
VueJS doesn't use web components as their foundation.
So you're not asking why. You're ignoring the question and burying your head in the sand.
