Landing page hypothesis testing is something which helps a lot and I have seen from very small to top companies like Amazon using it to validate their product ideas. It definitely helps to start with a landing page having a wait-list to see how many people are actually interested.

This initial indication is really important and can save you a lot of development efforts, may help you come up with better solutions and even reshape your MVP.

I do prefer to start my projects with a landing page due to these benefits, if I haven't already validated the idea.