Aside from Tesla=good, BMW=bad, how do you figure? Replacing a spring, whether steel or air, is normal for older cars especially those that come from harsh environments. My car in particular was older than any Tesla S is today when the air bags were replaced. The pump and electronics are still original.

Any Tesla that's had problems with its air suspension got a shorter service life than I (and plenty of other E39 owners) did. Besides Tesla's struggles with their conventional suspension components are well documented in a series of non-OTA recalls.