It's not a dragster.

That's no different than a FWD vehicle. The grip difference between the front and real axles (assuming you don't have staggered or different wheel sizes) is primarily going to be a function of of the weight distribution.

Most people in northern Europe know how to drive with 2wd (being able to drive in slippery conditions is a prerequisite for getting a license in the first place), so honestly that's more of an American issue than RWD issue.

And do you honestly expect a tiny economy car to have dual motor AWD? I thought you were advocating for FWD for some reason, not a much heavier and more expensive car. Just get a wagon or sedan if you want AWD. Tons of options out there and even more if you want an SUV.

And it can't be repaired in a minor collision. Those integrated rear wings are poor design for crashes. See insurance premiums.

I have no doubt AWD would be even better, but the weight of the i4, low centre of gravity, and traction control make it surprisingly excellent in the winter. Not sure if I'll ever buy new again (depreciation is a bitch), but I'd definitely look to jump to AWD electric. Plan right now is to drive this one for another ~6 years at least. The new i3 looks pretty damn nice.

Anything stopping you from running a more common tire size that's not officially correct for it?

Well obviously. But often those are typical issues you'd find for the model as they age. And he managed to buy 2 non-running i3s where the rex also wouldn't start. Cars not even that old yet.

I think the issue in the end wasn't even the rex, but the rex refuses to start if the stars aren't aligned. And if you're in the NA market then you can't even start it manually so you can only troubleshoot it by running the battery nearly flat when it's acting up. Which is why imo it's not a great extra and I'd rather take another car with a bigger battery if the extra range from the rex is crucial. The rex system had to be compromised for the car to retain its title as a BEV rather than a PHEV.