Curious how people evaluate companies tied to “future narratives”

Not limited to one company, but I keep seeing small firms gain attention because they’re connected to themes like:
Tokenization
Fintech
Digital assets
AI
Social platforms
The challenge is that many of them have very limited current fundamentals, so the investment case becomes heavily dependent on execution years down the line.
I’m not dismissing those sectors at all. Just wondering how experienced investors here approach valuation when most of the story is forward-looking.