That's kinda like saying a car is easy to build because they have automated painting robots. Fundamentally the problem is that most of the land they want to us

That's kinda like saying a car is easy to build because they have automated painting robots. Fundamentally the problem is that most of the land they want to use is owned by someone else, and that means every single parcel is a potential, and often actual, legal fight. In theory this is what eminent domain is supposed to accomplish, but people dislike eminent domain more than they like high speed rail. Well meaning but onerous environmental regulations don't make it any quicker either. When your rail plan goes through the nesting site of an endangered bird species or something that's another big legal fight. Even though the measure passed with a majority of the population, you have a situation where thousands of people have effectively a personal veto over it. Either their rights get trampled or the project doesn't happen.