Has been happening for at least 10 years.
What do you think the NSA is storing in that datacenter in Utah? Power point presentations? All that data is going to be trained into large models. Every phone call you ever had and every email you ever wrote. They are likely pumping enormous money into it as we speak, probably with the help of OpenAI, Microsoft and friends.
A buffer with several-days-worth of the entire internet's traffic for post-hoc decryption/analysis/filtering on interesting bits. All that tapped backbone/undersea cable traffic has to be stored somewhere.
encrypted with an algorithm currently considered to be un-brute-forcible. If you presume we'll be able to decrypt today's encrypted transmissions in, say, 50-100 years, I'd record the encrypted transmission if I were the NSA.
But is it big enough to store 50 years worth of encrypted transmissions?
Far cheaper to simply have spies infiltrate the ~3 companies that hold the keys to 98% of internet traffic.
If they actually worked, that is.
They would almost be failing in their purpose if they were not doing this.
On the other hand, this is an incredibly tough signal to noise problem. I am not sure we really understand what kind of scaling properties this would have as far as finding signals.