It's also more straightforward to get started and has sane defaults for the different "stacks" that exist. It's also way easier to self-host. So there are many positives for remix.
I would say if you know that you are going to use Vercel, use Next.js but otherwise I would always argue for Remix. I was a bit hesitant towards React before but Remix had me totally converted due to how easy it feels developing a full stack react app. Nothing even comes close in the javascript land imo. I have done years of work with SPA with web components/Vue/Angular and an api but using Remix I feel like I am several times more productive.
You don't need a state machine with remix as long as you use a backend (I haven't tried the new Remix SPA mode yet), even if you have a backend in another language it is a great way to do backend for frontend meaning that you can gather the data you need and provide it to the client in a nice way. No more spinners everywhere, let your fast server do the api calls and serve the rendered page to the client. You won't have the issues that usually comes with a SPA if you use Remix with a backend. You can stream stuff if you know you have requests that will take a bit longer to complete: https://remix.run/docs/en/main/guides/streaming
You can read more about why remix is nicer here: https://www.epicweb.dev/why-i-wont-use-nextjs