I was hugely sceptical too and have spent a fair bit of money on high-endurance enterprise grade SSD’s to use for backup purposes and external storage so am fully aware of the typical write endurance of consumer drives.
But as others have pointed out the likes of smartmontools have consistently verified the estimated endurance of Apple’s current ‘SSD’s’. They do use NAND from different manufacturers but the numbers don’t lie. There is a long thread about it on this very forum. Apple’s current storage is consistently rated for around one and a half Petabytes per 256GB of NAND. There are plenty of people with 256GB storage with well over 1000TBW.
And yes warranty rated endurance from OEM’s perhaps seems to be erring on the low side in some cases. I’ll admit that the whole thing seems slightly odd but going by ‘Occam‘s Razor‘ it appears that the NAND that Apple uses is capable of the write endurance that is being reported by the tools and the tools are reporting the endurance correctly and have been doing so since day one. If the Apple SSD controller in every single machine reports that the NAND is rated for 1600TBW per 256GB then that is correct and indeed has been verified by users. Not sure that there’s much room for interpretation at this point.
