Smaller teams can absolutely achieve similar. algoexpert.io is a nice example. A React app with TypeScript and a Go backend by a two person team.
The SPA scene is gargantuan now. Out of the top 3 (React, Angular, Vue) Vue is the easiest to learn and what you learn there will not be wasted if you move to React or elsewhere later. Svelte is even easier but has some ways to go.
If you are basing your opinion on what SPAs and these frameworks used to be like, give them another look—you might be surprised by what they can do and how much you end up liking them.