I believe when someone says "talk to people" they mean ask them what they currently love and hate about a competitor (to understand what makes yours different and how to attract people), and to gather some users / customers to understand what can be made better (as nothing is perfect at the beginning).

When you come up with some solution, you don't know it's an actual solution, it is filled with your assumptions.

The point of talking to users is to (in)validate as many of your assumptions as possible. It involves no selling or promotion or even demos when done well.