I really don't think his intention was to discredit amateur science by linking to the search results of "proof that amateur science sucks."
Well, it's sort of complicated.
On one hand—it's probably worth pointing out that the American punitive system is absolutely insane, and the mildness of this should not be taken as evidence of a defective process simply because it doesn't follow suit. Indeed, there are some fairly involved legal and philosophical reasons as to why the punishments aren't more extreme. Here is a paper on it. (I haven't read all of it, but it seems sensible enough from the first few pages.) One of the key points is that a lot of money goes down the toilet on dead ends and genuine errors anyway; another is that scientific misconduct isn't actually illegal, so the power of funding bodies to defend themselves is somewhat limited. In the end, the top priority is still getting them out of science.
What a strange question. Octave has quite an enormous userbase, perhaps not as big as R but with a heritage going back to the 1980s.
The real question is what can't you do in Octave that you'd do in Matlab: it's been quite some years since I used either, but I did have to port my Matlab code to use different or missing toolboxes so that it would run on Octave. The other big problem is a complete lack of integration with data/signal acquisition hardware which has drivers for Matlab (up to a crusty old version you've probably just retired)...
Never test for an error condition you don't know how to handle. -- Steinbach