A more generous take on the previous post is that the dominant paradigm of Math (consistent logic, which depends on many things like transitive preference) is wrong, and that another type of Math could work.
If you look at the slide, the subtree of correct answers exists, what's missing is just a way to make them more prevalent instead of less.
Personally, I think LeCun is just leaping to the wrong conclusion because he's sticking to the wrong tools for the job.