Why is 70% a end of life threshold? Considering that most major models are sold with configurations where the entry level begins under 70% compared to the "Long Range" model, clearly 70% is a perfectly fine level of battery for some users.

I myself have a 11 year old Nissan Leaf with pretty significant battery degradation (the guessometer says 70 mi range but I wouldn't count on more than 35-40) and it's fine for probably 95% of my driving.

If I were to buy an electric car with 300-350 miles of range today, I could easily see myself finding a ton of value in it in 20 or even 30 years. It's still more range than my current one! Lol.