Yes, that’s essentially what many philosophers call “the hard problem” of consciousness.
You can describe things using referential abstractions that are socially agreed upon between individuals in some sort of social contract.
However, we will never know if what you experience when you see the color we both call “red” is the same that I experience when I see the color we both call “red”. It could be that what I experience with “red” is what you experience with “blue” and vice-versa, but we still would agree when we both point a color, since the words we use to explain each of our experiences would still be consistent with the reference we have agreed on.
We agree on what words mean based on what references we make, but you cannot really ever be sure that we are both truly understanding each other in a subjective level. Each subjective experience is personal and nontransferable, you’d need to BE “me” to know what it’s like to BE “me”. And if you did, then you would no longer be “you” anyway… so that makes it literally impossible.
True. Also, it would be helpful to actually understand what kind of metadata is this referring to and specifically in which cases does this apply and which cases are exempt… because I expect that if the design of a service explicitly makes it so all the metadata you can collect is not helpful/reliable, then you wouldn’t be forced to redesign the service, you’ll just provide metadata that’s unreliable.
I feel these kind of measures never are really effective at stopping organized criminal activity (since those looking for a way will find it), what they are effective at is tracing/tracking non-criminal private use.