Svelte is definitely still my favorite way to build web apps in 2025.
I wasn't (and still am not) the biggest fan of the new Runes syntax, but I've gotten used to it, and it doesn't really hurt my productivity or get in my way that much.
There's definitely an ecosystem gap compared to React, but there are still lots of really good components and frameworks out there. For example, there's a native Svelte version of IBM's Carbon Design[1] which I've used and found to be very high-quality.
And as for arguments that React will keep winning due to LLMs not having enough corpus to learn less-popular frameworks, I've anecdotally had good success with using LLMs to edit and generate Svelte code. There are occasionally some issues (like it generating pre-runes syntax or using deprecated stuff like stores) but it works well enough to be useful, and definitely better than I expected.
You might be happy to hear that we're releasing a new version of the Svelte Society website to make it easier to find packages and other resources. We're currently migrating data and fixing bugs but if you want to give it a whirl you can find it here https://prod.sveltesociety.dev until we switch it over to the root domain.
Of note - Svelte publishes documents specifically intended for LLM consumption, https://svelte.dev/docs/llms
Making my LLM aware of these documents significantly mitigated issues I had with adopting Svelte 5 syntax.