I agree with you. When a product or working prototype, it gives more confidence in the successful completion of the project. After all, before the ICO to create a prototype, the company worked and found investments, it means that it really works, has experience, knows the weak points of the project and will overcome them.
ICO without product are like a scam
Right, it is this product that would make the objective of the coin or token come into play, make it useful, drive in demand and of course increase the value of it over time. However, most people are always looking for the easy way out for quick bucks, when the real investors are getting richer with good solid projects.
Once there is a product, there is a future and how much you believe in the relevance of the product, determines how well you decide to invest in it.