How is it nonsense? Vision doesn't matter - customer feedback matters.
You start off with a hypothesis (X will solve Y's problem by doing ...), you build a prototype, and then you start testing with multiple Ys. Based on that feedback, you then tweak your initial hypothesis or you scrap it and pivot.
The whole point of engineering is to build tools that solve a specific class of problems for the buyer.
Most people are not Steve Jobs, and do not have such a vision. Or the ability and capital to see such a thing through to the end. Steve Jobs also had a number of visions that didn't work out so well too - he learned and interated from them.
Thus, for most folks releasing a product and getting to market/revenue is more important than anything else. Then iterate from there.
YMMV of course. But the older I get, the more I realize "just get it done" is far more important than almost any other metric there is. There is a ton of navel gazing in tech that provides negative value. If I had released some of the things I worked on in the past vs. carefully designing and polishing them, I might still be working on them today. Competing products have maybe 50% of the "quality" of even my prototypes of 10 years ago - but they exist in the market and are used every day by customers to generate income.
You start off with a hypothesis (X will solve Y's problem by doing ...), you build a prototype, and then you start testing with multiple Ys. Based on that feedback, you then tweak your initial hypothesis or you scrap it and pivot.
The whole point of engineering is to build tools that solve a specific class of problems for the buyer.