That said, it is relevant that they only do this for "deactivated" accounts, and not "deleted" accounts. To give them the benefit of the doubt, those states are different, and if they communicated what they meant by each state, it would be fine with me if they continued tracking people until they actually deleted their accounts.
The problem is that they don't communicate it very well — they didn't back in 2008, and it sounds like they don't do it much better today. That's the sneaky part, not the tracking itself. Well, the tracking is sneaky, don't get me wrong, but if you're on Facebook in 2022, you must know about it and have accepted at some level that it is happening.
I also remember actually getting them to delete my account for good was not trivial. There was a waiting period, and a lot of different ways to accidentally opt out. To be honest, I initially read this article thinking it had been discovered that they were tracking "deleted" users in addition to "deactivated" users this whole time, and it didn't surprise me at all.