I would imagine they have tried, but the thing is completely destroying data….. is not as easy as “wiping it with a cloth”.
Like deleting a comment on X, by the time you do that there are many copies of it elsewhere.
Forensic investigators can find an t lot of what has been “deleted”.
I can only hope
If the FBI no longer has it, the NSA would. If it’s electronic comms, they hoover it up.
Now, this is a pure conjecture but wondering if in the last few years, white hat folks started collecting information and squirreling it away, or put in a separate surveillance system for IT systems, hoping to catch folks trying to cover tracks?