I just finished watching the entire proceeding, with a few short rewinds.
I'm appalled even at the suggestion that because the government thinks it "needs" to do something, it can. This theory permeates several of the points made; it is invalid from the ground up. If the government believes it needs something that is constitutionally prohibited, its remedy is found in the pursuit of the processes laid out in article five of the constitution -- not in outright ignoring the hard limits set upon it by the bill of rights or other sections of the constitution.
Likewise, the "is it reasonable" sophistry was very upsetting to encounter again. It's an outright stupid tack to take. The 4th does indeed include the word unreasonable, but it then proceeds to describe what is reasonable: probable cause, supported by oath or affirmation, may cause a warrant to be issued though that warrant must be specific as to place(s) and item(s) to be searched for. Those conditions all being met, the search is then both reasonable and authorized. The fact is, if all it takes is someone saying "well, I think it's reasonable that we search fyngyrz premises (or whatever)" and this over-rides the very specific instruction that a warrant is required, then the entire 4th amendment is without any meaning at all other than perhaps, optionally, advisory.
On the subject of who can search what...
If I hire a house-helper to whom I assign the roles of answering the phone, keeping the larder up to date, cleaning and laundering, this person clearly has my permission to search. They will search under furniture, appliances and cushions for debris; they will search cabinets and the refrigerated devices for out of date or missing foodstuffs, they will open my drawers and organize and store my clothing. They will, in large part, know who has called me on my home phone, and who I may have called out to.
Fine. I can give such permission. But this, in and of itself, in no way serves to authorize the government to search my premises -- for anything. The 4th limits the government with regard to my person, houses, papers and effects. It does not (obviously) limit me, or someone I hire a service from and extend such permission to, from searching. The 4th is clearly not limiting action in the public sphere. It is limiting action in the government sphere.
Relating this to Verizon and its peers: By contracting to make phone calls through their capabilities, in no way have I extended the government access to my communications, in any part or parcel. What I have done is arrange for a service by Verizon/peers without extending the government any permissions at all, and the government, absent my explicit permission pretty much identical to that as given to my house-helper, is restrained, intentionally so by the 4th amendment from searching for anything, anywhere, in regard to my communications. Which, in case anyone is wondering, is also the rationale that underlies title communications law with regard to the content of my calls, and also forms the basis for the prohibition of any person monitoring cellular radio links.
Every time the government succeeds in arguments from need instead of authorization, we become subject to the whim of individuals, rather than to a constitutionally limited government. It should frighten the living daylights out of anyone who understands the issues when the rationale is "but we NEED to", as was seen multiple times in the government side of this proceeding; and the more so when the judges don't laugh in the face of the person presenting that argument.
Remember: If the idea is that the constitution is merely advisory, then there is no functional difference between the US government and that of any tin pot dictatorship. Someone says "I wanna", and it happens. That's most definitely not how our country was intended to operate; otherwise the framers were completely wasting their time.