So true. The battery itself has overdischarge protection. 0% reported by the BMS still [typically] is considered acceptable normal state, and that’s different from absolute 0v on the cell.
I re-calibrate the batteries in my ThinkPads typically around every 4-6 months. I’d say the wear while does exist, it is usually not a point of concern even over a period of 5 years.
Here’s a recent re-calibration, just for reference, thought it was noted that the battery cell package type does make a difference to the longevity of the battery:
With the puffy batteries showing up on the forum, I’m slightly disappointed that we’ve created more e-waste in this regard than would have typically otherwise (with or without warranty replacemnt).