The grid upgrade can cost millions for a DC fast charging station.
The inverter to make the DC power can cost 100,000.
Why not skip all this and have a diesel engine coupled to a 400V DC generator, thereby skipping the inverter and grid upgrade?
I think this would be cheaper, and lower capex and operational costs. Not to mention, most streets have natural gas lines which could power the diesel engines with a cheap and clean burning fuel. Natural Gas is very cheap around 4c/kwh. A 20% efficient generator, would yield 16c/kwh.
That would cost even more.
Probably the same reasons the vast majority of electricity users decide to hook up to the grid instead of generating their own power. Or, put another way, the reasons a connected grid exists.
I’m far from an expert so it’s hard to really disprove your assumptions , but you make an awful lot of them. But I’d question costs of equipment and fuel. I’d question whether a diesel generator makes sense for a highly variable demand like DC fast charging. I’d question the emissions and efficiency. I’d question a lot.
Low quality trolling aimed at stirring the pot to no useful purpose.