Your understanding of how the route affects the price is misguided.

It has nothing (or very very little) to do with how difficult the terrain is to navigate, it has everything to do with who owns the land, and how much they want to charge for it.

Often these "owners" only purchase the land once informed that it is a potential high speed rail route.

They will do the same to a different route. Once you buy land you become committed to a route. Reform is needed, but I'm not sure what.

In a way, it’s a transfer of wealth from masses to these land owners (or brokers in a sense).