I'm not really assuming much malice there. I am assuming malice in how they'll use the data, but given their past track record of removing features based on telemetry data, I don't think I'm making too big a leap.
telemetry used to be opt in, it's been changed to opt out. And now those who have opted out have their own special telemetry that cannot be disabled.
This whole discussion shows an absurd lack of perspective by some people, particularly in the light of what Chrome does... or what Android does... or what LITERALLY EVERY SINGLE TCP CONNECTION TO LITERALLY ANYTHING ELSE ON THE INTERNET does...
Would it feel less "[sneaked] in" if this were a core feature in Firefox?
The effect of malice is frequently separate from the intent of malice.
There's quite a long string of such events that points to either cluelessness or malice.