Given this, I'm curious: couldn't the traditional syntax of `let counter = 0` be made to function similarly to the new let count = $state(0);? Transpile it to let count = $state(0) under the hood? If that can work technically, instead of introducing a new rune for reactivity, why not introduce a "negative" rune to denote non-reactive statements? This way, the change wouldn't break existing code; it would be more of a progressive enhancement.
I agree the move to unify the Svelte <script> tag with regular js/ts files is an improvement. It was indeed a little odd that certain syntactic sugar, like the $, would work exclusively within the Svelte <script> and not in a js/ts file that's right next to it. However, from what I gather, it seems the Svelte team is aligning the Svelte script more with js/ts, rather than bringing the js/ts closer to Svelte's unique syntax. This trajectory seems to be pushing Svelte towards resembling traditional JavaScript frameworks, like React. It's a departure from Svelte's unique strength of having a custom compiler and behaving more like a language. If every syntax in Svelte is expected to mirror its behavior in js/ts, eventually svelte will lose all it secret sauce that made it so unique. Why can't we add a rune into js/ts file, a note in the beginning to tell svelte compiler that this is svelte enhanced js/ts file, compile it like svelte script tag code? Bring js/ts more alike to svelte?