There are many reports of them lasting for years and mega mileages. But those are cars in regular use.
I suspect that when cars with EV batteries become older some may become a second or third choice 'old banger ' (or old sparker'

) which families or businesses might leave lying idle for long periods .This could quite quickly permanently knacker their batteries. And you wont be able to recommission them just by replacing a relatively cheap lead acid battery.
Hopefully this wont affect me personally. I dont plan to keep it 14 years as I did my Diesel Yaris. And maybe by then there will be more specialists able to refurbish EV batteries for not much more than the costs that ICE cars are prone to, (but not Ev's) such as a new clutch .
I think old ICE cars will remain sought after and hold their value for a while because of their go anywhere, range anxiety advantage ,etc and Hybrids too as a compromise. By the time new EV with more efficient batteries become affordable for budget buyers most Hybrids and early EV's will have reached the end of their natural service life anyway and start to appear in scrap yards for reasons other than their battery.