Have you done this successfully yourself? You’re saying the opposite of what many people with startup experience recommend.
I found out why ‘build something great and they will come’ is usually not true, the hard way, by blowing my own savings along with other people’s investments doing it. Great products almost never go viral on their own, they need tons of iteration and feedback. Most developers who have a truly great idea, including yours truly, don’t understand that their great idea doesn’t appeal to most people, or like in my case that people like the idea but they each have 3 different things they consider much more important, and you can only find out which great ideas have mass appeal by talking to a lot of people.
Normally, the wise startup advice is to listen deeply to a lot of people, to not jump to implement exactly what they’re asking for, but hear more broadly what their problems are and what they need. The advice is not to stop listening and ignore them, and it is not to consider listening a waste of time, the advice is to listen first and then read between the lines.
‘Build it and they will come’ is practically an anti-meme in the startup world, you can find tons and tons of examples of this failing to work, and tons of examples of wise people with experience advising to get this idea out of your head ASAP.