When they made the changes to the s boxes for differential cryptanalysis resistance the entire concept of that was essentially secret, so who knows what they know about elliptic curves.
> If that many curves are bad, then ECC was a mistake.
I mean that is the logical conclusion from the behaviour around this approach where a few good things are effectively endorsed without justification.
The fact is any application of an algorithm that involves so much "trust me bro" on the selection of what are a large number of opaque quasi random but not quite or provably so numbers only has as much trust in it as you have in the people that created it.