If that was the only thing you got out of his post you clearly were not reading it well enough.
They do test their code on different machines. That is why they put out Alphas and Betas. That is why AdamW actually does work for QA. But even that will only cover a small fraction of the machines the system is likely to be ran on.
I somehow doubt that this was done completely from the ground up, but even if it was, they posted a very lengthy and reasonable rationale as to why this was necessary and followed a very strict and cohesive road-map. It was not like, as you assert, some kid came in and brashly claimed they could do this better. That kid sounds a bit like you though.
I thought it was explained that it was because of the way that the old Anaconda used it's interfaces that it became problematic to maintain. Maybe I got that impression because I actually went through all of his posts?
BO$$ - always grabbing on to one easily demonstrated false assumption and running with it.
