If you use a bunch of libraries for routing, UI, authentication, the only thing thats left is the rendering.

And quite frankly I don't see why Id want to reinvent the wheel there.

{#each notes as note} {note.content} {/each

is exactly what Id want to implement for example if I were writing JS functionality to render a collection.

And Svelte for example doesnt restrict you from using vanilla JS whenever you want either