Tbh, I often wonder the same thing. I've been using the Next.js + Firebase + Zeit stack lately and I can tell you: it's been a great experience so far. It's really easy to manage, especially as a solo dev.

As "jmnicolas" mentioned, though, I think "The Boring Stack" is often the best choice. Don't spend too much time on what the "thought leaders" on Twitter saying. Just use whatever makes you move faster to get shit done. Once you have some paying customers, you can always go back and change things.

I think the most important thing as a solo dev is just understanding what your possible customers need. You can do that using whatever tools work for you.