Has a recycling program =/= everyone who ever purchased an iPhone is using that recycling program.

7.8 million "Apple devices"[0] in 2018 is a lot, but an average iPhone is far more likely to end up on a landfill. If it were easy to extract the battery, that wouldn't be such a problem.

[0] They group them all together and I can't find any other metric: https://www.apple.com/newsroom/2019/04/apple-expands-global-...