I never said that those weren't problems, but from a legal and logical perspective, I think that they are less likely to defeat the proposal than my argument, because there are situations, like at airports and even Copyright law in some jurisdictions, where you already are treated like a criminal by default. People aren't challenging those laws likely because the notion of proportionality is subjective, however it is almost universally agree that transparency is absolutely vital to promote a healthy democracy, and that it is only permissible to hide information from the public when it involves national security, which is not the case here.

The biggest problem with this kind of legislation, in my opinion, is the lack of transparency. Without being able to verify the algorithm used, and the kind of information that can be collected, I can never be sure that my rights are being respected. On the other hand if the process is transparent I can easily find ways to circumvent it, so this kind of legislation doesn't make sense unless it's intended as a slippery slope to make end-to-end encryption completely illegal.