They don't. There's an element of artificial/forced "futurism" in their appearance, generally: rounded bits in the wrong places, weird curves/shapes to trunks and lights, etc. Not to mention the poor and shoddy interiors. Tesla looks like it was going for a hospital surgery room level of sterility in the cabin--no thanks.
Almost all of them look exactly the same as petrol or diesel cars. Sometimes the grill looks different as they don't need air-cooling. Is that a big deal?