It isn't just more rubber on the road that makes wide, low profile tires have higher performance. In fact, all else being equal, increasing tire width trades a narrower, longer patch for a wider, shorter patch of the same contact area. See this Video. The other benefits of wider tires are needed for a Taycan and not so much for a BMW i3.The theory of narrower tires providing more weight is probably moot for EVs which put down a ton (or rather tons) of weight already. In the end, width not making much difference on snow and ice, it will definitely make a difference in dry and wet - wider means more rubber on the road - if that was not true, Taycans would be riding on super narrow tires to increase range.
This is very true, a narrow but long contact patch has many advantages over a short wide one for stability, control and camber sensitivity. Tyre diameter was restricted in the F1 rules because of this, punters like the look of wide low profile tyres and that is therefore what the manufacturers wanted to spend development money on.In fact, all else being equal, increasing tire width trades a narrower, longer patch for a wider, shorter patch of the same contact area.