I believe Kia recognized the fact that many batteries were failing and would soon need replacement years ago.
It helps understand why Kia stopped selling EVs in the American market and focused almost entirely on Norway.
Norway - the one place where climate and driving conditions mean a substantial number of battery packs will survive.
There have been reports of failing battery packs also in Norway. As some owners has had their cars 5 years (first cars were delivered autumn 2014) many owners has reached 100.000 km (appx 60.000 miles) or more. I don't know the percentage which have claimed replacement, (Norw. warranty: 70 % capacity after 150.000 km/7 years), but my impression from Norw. EV forums/Facebook groups is that a lot of owners of the cars which have passed 100.000 km are experiencing degradation problems. Some have had their battery packs replaced after waiting up to 6 monts on a new pack.
My car (registered November 2014) started showing signs of degradtion at appx 80.000 - 90.000 km and according to the Soul EV Spy app, SOH is now at 76,1 %, down from 82,1 % just a few months ago. It seems degradation is happening faster now than ealier.