One is what the general public thinks about the importance of metadata; the OP shows that it is a bit more than some may think, so arguing about the legal aspects is a bit beside the point.
That said, if you want to argue the legality, it isn't that clear-cut, either. The problem is that while Smith v. Maryland may resolve the question of the constitutionality of the collection, it does not answer the question of its legality. In addition to a search or seizure being constitutional, there generally also needs to be a statute authorizing the search or seizure.
Unfortunately, whether there is such a statute is highly dubious. The leaked court order used an extremely suspect interpretation of section 215 of the Patriot Act to justify seizure of the phone records; which is what Senators Ron Wyden and Mark Udall kept pointing out. Seizure under the electronic surveillance provisions of 50 USC §1801 etc. does not solve the problem, either, because 50 USC §1801(n) defines "contents" for the purpose of electronic surveillance to include metadata. And seizure under the Pen Register Act would require the government to certify that the information obtained is likely to be relevant for an ongoing criminal investigation.
This means that while Congress could have authorized the NSA to collect the connection data in such a fashion without such a law being unconstitutional, it is at the very least questionable whether Congress actually did such a thing.
One is what the general public thinks about the importance of metadata; the OP shows that it is a bit more than some may think, so arguing about the legal aspects is a bit beside the point.
That said, if you want to argue the legality, it isn't that clear-cut, either. The problem is that while Smith v. Maryland may resolve the question of the constitutionality of the collection, it does not answer the question of its legality. In addition to a search or seizure being constitutional, there generally also needs to be a statute authorizing the search or seizure.
Unfortunately, whether there is such a statute is highly dubious. The leaked court order used an extremely suspect interpretation of section 215 of the Patriot Act to justify seizure of the phone records; which is what Senators Ron Wyden and Mark Udall kept pointing out. Seizure under the electronic surveillance provisions of 50 USC §1801 etc. does not solve the problem, either, because 50 USC §1801(n) defines "contents" for the purpose of electronic surveillance to include metadata. And seizure under the Pen Register Act would require the government to certify that the information obtained is likely to be relevant for an ongoing criminal investigation.
This means that while Congress could have authorized the NSA to collect the connection data in such a fashion without such a law being unconstitutional, it is at the very least questionable whether Congress actually did such a thing.