Really depends on how much you weigh CO2 emissions, different air pollutants, noise pollution, etc. Environmentally friendly isn't a single dimension.

Furthermore it's not like he's going to dispose his older car, it's going to go to somebody else who might have an ever older, more pollutant car.

No, probably not. An EV car is approximately 1k gallons of gas in energy to produce. Of course there are also rare earth metals. But your claim is obviously untrue at the edge, where that car could be driving 24k miles/year at 12mpg, for 30 years, and the EV is charged by renewables. That’s an extra 60,000 gallons of gasoline to account for with just the production cost of an EV.

That’s not if you are going to junk your car rather than resell or use it for another purpose. If your car is good enough to be resold, the damage is limited unless the buyer of the used car wouldn’t have otherwise gotten a new or used car. But induced demand is a thing, if all rich people kept their cars for 10 years, the used market would be decimated and a lot more people would take public transit, so there is that.