The point is, they "proved" the Collatz conjecture. You would not know they exploited a bug unless you actually went and dug into their proof. Can we be so certain this has not happened within the millions of lines of Navier-Stokes? In an ideal world, our proof assistants would be more battle-hardened by now (recent exploits deny this), our AI better aligned (their tendency to cheat at tests denies this), or their handlers more responsible (the Hugging Face incident denies this), but the reality is more complicated.

At this point in time, we really can't be confident in accepting proof certificates without any human eyes on the script that generated it. I still have 95%+ confidence in this particular result being trustworthy, but a precedent of blind faith is guaranteed to end badly.