> it's not very difficult to put some cables in the ground and install a big pre built metal box :)

But increasingly it's becoming a problem that those cables have nowhere to run to as the grid isn't capable of serving them all. There might be excess generation but unless you have the capacity in the wires to get it where it's needed you're still stuck.

Especially in dense old cuties where the grid was built when the goal was to power a bunch of incandescent light bulbs. Not all the appliances we have today let alone cars with a battery capacity equal to a household's weekly usage of electricity when the grid was designed.