Exactly! That sounds like a drawback when you state it like that, but what it actually means is that this magic battery doodad needs to provide 90-95% of the performance of its existing, mature competitor (assuming no other drawbacks) just to be break-even in the market. You don't disrupt markets with numbers like that.
The problem is mostly that it does the battery draw when parked.
Solid electrolytes are coming some day soon, so that we can let it freeze without killing the cells.
Right now, the Tesla is hard to use in a winter sport season unless where you're driving has a charger or underground parking near a plug point.
I can drive up hill to a nice ski resort, spend 3+ days taking the bus with all your shoes on without touching the car.
With the batteries, they'll just run down when parked, so I cannot park it for a whole week outdoors like I can do with my Subaru.
And with the low battery + low temps, it will not charge back up going downhill so the expected range drops massively by the time you're downhill.
Once you navigate to a charger, the car starts running the heater and driving down range further.
Watching the car battery eating its own range while driving to "Donner pass road" on your way out of Tahoe or Reno feels rather appropriately horrific.
What kind of clunkers have you been using that lose charge on the 12 volt after just 3 days in the cold? I've occasionally left my ICE car out in the cold for a week without using it and it never once even crossed my mind to worry about whether it would start after that; I've never had that issue on any car built in the last 15 years.