A waitlist becomes useful when you treat it as more than a list of emails. The people who join can actually become early testers, interview candidates, and a source of honest feedback about what problem they expect the product to solve. That said, I’d still be careful about confusing interest with demand, because clicking “Join” is much easier than actually using or paying for something.

The interesting approach might be a middle ground, keep the waitlist small and use it as a testing group, while still launching early enough to learn from real users. That way, you’re not spending months creating hype around something that hasn’t been tested yet, but you’re also not opening the doors completely cold.