A self modifying intelligence would need metrics to tell if it was improving or not.
This would require huge sets of data...and a way to compare them. We can do that, but it's not efficient at all.
In the 80s I thought a computer doing face recognition was impossible: a photo is just too much data to process.
We've solved this problem in the least exciting way. A kind of brute force. Throw more servers at it. Yes some of the algorithms are nice... but it's not exactly magic. 4/