Based on my firsthand experience, cold weather (big one) or hauling/towing significantly reduces that 400 mile range (sometimes by 50%+). Yes to comfortably get 400-500 miles per charge in the worst case scenario it needs to be atleast 2x.
I recently did a day trip of 800km while it was freezing and snowing. Yes the range is impacted, so i never did more than 200km in one go. Then a quick 15 minutes break to recharge and continue. It takes a bit longer, but not bad enough to go back to ICE cars. EV drives so much nicer.
No need to double twice. 250 miles (~4 hours of driving) is about what you want. Pretty much everybody needs to bathroom at least that often. And nowhere on a road in the continental US is more than 150 miles from a charger.
So yes, you want 400-500 miles of range, but that's because you've doubled the 250 for weather, safety margin, etc.
If you're saying 100% only EVs with no use cases whatsoever for gasoline, then I suppose so. I don't think that's a smart goal, though.
More like, more people should understand how EVs can easily work for them, and then try to shoehorn gas-powered vehicles into the few niche they need to be in.
How often does someone need a 400 mile range again? Towing? When is the last time you towed something 400 miles? The most I ever towed was... using a rental truck and a rental trailer when I moved. (Anecdotes are not data!) But why in a rational purchasing decision would I need an 800 mile EV battery for a car just because sometimes it's cold out?