I think you'll be saving more money on running an EV then a ICE. Which is another reason why they like them as taxis.It's not the only reason, but I derive greater satisfaction from spending my money on other things than a car.
Any way my point is fuel cost is only a small part of the advantages of an EV. It's another value added. Unless you're doing mega mileage. Which we know from the data the vast majority of people aren't doing.
If you want to avoid depreciation and expensive cars don't buy an expensive one, especially not new. That applies regardless of fuel type.