No, perhaps you are not familiar with qualification testing that is routinely done to validate performance and life. One does not have to wait ten years in order to determine if batteries will last ten years. That's the whole point of validated testing - to get legitimate answers sooner. In this instance, they will run worst-case cycling of charges and discharges at temperature extremes, with vibration testing, to get an accurate idea of performance.Lab / track testing has proven to miss problems many times. Yes, there are sufficient numbers now to tell us something by 2030. As for mainstream cars and the value of one after the battery pack dies, we will get that 10-15 years after the first $25K MSRP BEV that sells well goes on sale, something that could happen within the next 5 years.. So any honest jury is out until at least 2035 on that question.
Any estimate on replacement cost is just that, an estimate, because we don't know supply and demand in 10-15 years.