Earlier quoted context omitted.
Snowden had the element of surprise. They weren't actively trying to monitor his comms because they didn't know he was a risk until after the leaks. If the state wants to decrypt your messages badly enough, they have resources that they can devote to that (as well as multiple side channels that are probably easier than forcibly decrypting, including the infamous "beat with a wrench" trick). It's not trivial to defeat…
Is there any evidence that any actor in the world is (in general) capable of figuring out the contents of e.g. an AES-encrypted message with the key unknown, assuming good opsec and a good implementation? I agree with your statement that state-level actors have strong capabilities, but this seems like a blanket statement which is likely untrue.
However, there are so many ways to circumvent encryption that it seems that there aren't a lot of cases where a hard decryption of a previously-coded message would really be required (the target can often be compelled or tricked into giving up his keys, a plaintext version may be intercepted at some point, etc.).