That really applies to the UK Government here and though the Police would want this I very much doubt that they even begin to understand what it is that they are asking for.
If we go back a Long Time to the Time of Cavemen Troglodytes and Cave Women in 2001 the US Authorities had recordings of the Hijackers conversations who where responsible for hijacking the Airliners Involved on 11 September 2001.
What they didn't have was the resources to actually scan these recordings so that they had any Intelligence on what was going to happen.
What the UK Government at the behest of it's Police Forces is looking at here without understanding what it is that they are asking for is
Information Overload. The only thing to come out of actions like this will be a reduction of staff on the streets doing the job that is expected of them more staff behind the scenes flooded with Information that they can not hope to even scan within the next few years let alone actually get any Intelligence from and the Bulk Waste of Money.
There are way too many Key Words that will trigger recordings and things like Boot & Nuke a common HDD Wiping Utility is just one of them that will require every reference to those 3 Words to be Manually Scanned for information to what it is referring to. While it could be a Dirty Bomb
again another key Word Combination it is just as likely and actually
Far More Likely to be an Invoice from a Computer Repair Company indicating why the bill was so much and have nothing at all to do with Terrorists Activity.
The only possible place that this would conceivably prove useful is in Criminal Cases and even then to recover the Evidence will take several years and cost Millions of Pounds that could better be used elsewhere to get the same conviction for far less and far quicker. Currently the Authorities don't do Data Recovery on Wiped HDD which they are all capable of performing because of the cost, and that cost pales to insignificance when compared to what is being proposed here. As things stand today any Government can Forensically recover any Intact HDD for somewhere around the Million Pound Mark, but what is being suggested as required is several Million Pounds being expended for every Man Woman & Child per year to save this Data and then somehow being worked through which to date is still undiscussed/comprehended by some Organization which as yet doesn't exist and as yet are not funded. And that is without any Legal Argument on if this Evidence will be Accepted by the Courts or thrown out as Not Obtained in Accordance with Existing Laws.
Yep makes perfect sense to me and sounds very much like Censoring the Internet, like is being proposed by the AU Government, though that while not overly piratical is infinitely cheaper than recording everything.

Col