The fastest supercomputers are capable of cracking at around 3 trillion passwords per seconds
I’m guessing that based on password hashing, hashing algorithms are significantly faster than AES which is the basis for the iteration here. Nevertheless, given a computer which does 3 trillion AES keywrap iterations / second, the average time to crack one AxCrypt-encrypted file password as mentioned above with it’s own strength of about 75 bits, with the 5000 round minimum in effect, is about 50 000 years.
If you use an even stronger password, then of course you get more margin. After all – we’re actually effectively only using 75 out of the 256 bits available in the algorithm key with passwords of that style. (A little more to be exact, since there’s also the 1000 iterations in the PBKDF2 function). You should probably add a factor for that above, giving 50 million years. But it’s always good to be conservative!
As you say – attacks are only getting better, that’s why we use the current hardware to scale up the strength as hardware gets better, so we at least keep pace with that.