Manufactured products only get cheaper by scaling and improving the manufacturing process. You should know this because it's the reason why silicon photovoltaics have gotten cheaper after starting at some rather eye watering prices. Land is a finite resource with an extremely complex system of regulations, laws, ownership, uses and speculation built up over 10,000 years of history and any conversion of land for one purpose necessarily excludes it for many other purposes so there is massive competition over prime real-estate and many un-intended future consequences resulting from development.

Not worrying about land use when it comes to power generation is very, very much like not worrying about carbon emissions when it comes to power generation/transport/manufacturing "The atmosphere is enormous! Why should we worry about emissions when our current demand for power and transport is so tiny?"