I'm inclined to agree in principle that such tracking should be opt in.
In practice, I'd expect the behaviour of the modal complainer to be: 1. to complain about any broken/removed functionality 2. refuse to fix it themselves (or fund the fixing) 3. refuse to opt-in to tracking so as to give impartial of usage.
So I think the trade-off of default analytics where the volunteer contributors make a best-effort to keep things working for as many people as possible is beneficial to most users. (And for those who disagree, they can opt out).
In practice, I'd expect the behaviour of the modal complainer to be: 1. to complain about any broken/removed functionality 2. refuse to fix it themselves (or fund the fixing) 3. refuse to opt-in to tracking so as to give impartial of usage.
So I think the trade-off of default analytics where the volunteer contributors make a best-effort to keep things working for as many people as possible is beneficial to most users. (And for those who disagree, they can opt out).