1957 was the peak year for US streetcar ridership. Till about 1970 the bus lines, tramlines, streetcars, metro transit etc were the back bone of commuting for vast majority of the public. For sure they were undermined by illegal cartel and collusion between Firestone, Ford and Standard Oil. But do not ignore the role public and the politicians played in getting rid of these public utilities.
Structurally these utilities need massive insvestments, long build times, beset by NIMBYism. They pay off only when there is a critical mass of users. Only when the cost of investment is amortized over a very large user base, these projects are economically viable. Once the user base falls below the critical mass they get into a death spiral. Costs keep increasing for the remaining users, and as they drop out, it increases for the remaining users even more.
Electric utilities are looking at exactly the same scenario. In 1955 if someone predicted the demise of street car lines within 20 years, they would have been laughed at. But in 20 years almost all of them became moribund. Except for very high density locales like Chicago, Boston and New York it is mere shadow of its former selves.
As solar becomes cost effective, finance companies will jump in and simplify the financing and installation headaches and make direct head to head comparison possible. "All you pay for is the electricity you actually use based on the meter. All you do is to give us permission to install solar panels in your property. Compare it directly with your utility bill". As affluent customers start using more of solar and use less of the grid, the utility company will start levying "grid-connection fees". And at some point people would start cutting the grid. Then cost will start going up for the remaining users and the spiral would start.
The electric utilities are well aware of the situation. That is why they are fighting so hard.
One way out of their plight is for the utilities to start installing more and more of solar. Solar generation neatly matches the peak demand. If they can use solar for peak summer late afternoon demand and run their gas plants for base load they can survive or stretch it out for a long time. But no matter what, coal is out. Even dirty coal is costlier than gas, not much cheaper than solar. Clean coal just can't compete.