Its comical that you think its a “problem for Fitbit”

Well, if I don't buy a Fitbit who has the problem ? Me that buy another brand device or Fitbit that don't sell one device (and as consequence also loose the option to gather some data) ?

Also, that’s not “thanks to the GDPR”, as itn doesnt prevent data collection when you’ve consented to it, which the overwhelming majority of people happily do.

True. The point of the GDPR is allowing people to be able to decide who and when share their data without fearing something like "If I sell you something you are forced to give me your data".

Look, there are only two options: 1) you sell me something knowning I can deny your data collection and 2) you don't sell me anything from the start.
In the first case, you have a sell and maybe have my data, in the second you have nothing and I have sothing from someone else.

But let's end here. I understand that we are not thinking the same. Nice discussion anyway.