Yes, it really is. Startups these days aren't using traditional rails anymore as much as either full-stack typescript w/ React (a la Next.js) or Next to make SPA and hitting a more full-featured REST API.

There is currently a lot of cutting edge engineering focused on the Typescript ecosystem (Vercel, Cloudflare, Deno, etc) vastly outpacing things being done around Rails, Django, PHP, etc.