It is not economical compared to alternatives that is why you have to have government to force people to do things. In many places such as Pakistan where solar power is not economical on paper is actually very successful in practice because it is actually profitable.

To make solar power practical and economical you need may a square foot of solar panel being able to get enough energy to power and entire home for a week

https://www.statista.com/chart/35117/levelized-cost-of-energ...

Not sure what you’re talking about here. We can’t replace all energy needs with solar but it’s clearly one of the cheapest energy sources and with the added benefit of low capital expense to get started so you can set it up in distributed grids without the massive expenditure to support nuclear installations.