It’s certainly true that you should launch something as soon as is reasonably possible. This is so you can get into a customer feedback loop and start iterating

It’s certainly true that you should launch something as soon as is reasonably possible. This is so you can get into a customer feedback loop and start iterating on the product to improve it and build a better product with actionable information. However, how long it takes to build a reasonable MVP depends on a whole lot of factors, like existing competitors, target audience, scope of product, industry, etc etc. some simple saas products can take only a few weeks to build, but if you’re in the aerospace industry a prototype will take years if not more.