Sure, but when the overall degradation is pretty minimal, this doesn't matter terribly much. I'm at 96.5% rated capacity after 12K miles. That's pretty typical. I should be down near 90-93% capacity at 100K miles. I probably won't keep this car long enough to get down to 80%. At that point I -might- consider replacing the battery, but given how old the car will be, it's not too likely. The only way the battery ever gets replaced in this car is if it fails altogether.
Right now if I had to pay that out of pocket it would be more than a new engine, but not by a huge amount. By the time I don't have a battery warranty, the cost will most likely be in line with a used engine for a similar ICE car.
Problem how? That sounds like the opposite of a problem to me. Everyone is used to a car massively dropping in value immediately after purchase. If the battery drops right away and then that slows down a lot, you won't need a replacement for a very long time.
Politics.