Flights are a good example but I often cite Uber as a good one too. Nobody wants to tell their assistant to book them an Uber - the UX/UI is so streamlined and easy, it's almost always easy enough to just do it yourself (or if you are too important for that, you probably have a private driver already). Basically anything you can do with an iPhone and the top 20 apps is in this category. You are literally competing against hundreds of engineers/product designers who had no other goal than to build the best possible experience for accomplishing X. Even if LLMs would have been helpful a priori - they aren't after every edge case has already been enumerated and planned for.