In theory of course this should be the case, but in practice this is terrible advice IMO. There are tons of great successful businesses that wouldn't have passed this test.

Did anyone really need the early AirTable? No, you could just use Google Sheets. Did anyone really need WhatsApp? No, there was texting already. And so on.

In theory everyone should stay far away from building "nice to have" products and only solve hard business problems but that is a super high standard that even most companies that are already out there probably don't meet.

Of course, getting feedback and adjusting your vision is super important though and sometimes a radical pivot is needed.