Seriously? You undermine your own argument with that comment.
If the CPSC is doing its job well it will react towards gadgets that are within its domain and statistically shown to be dangerous. Regardless of how you feel about this agency's actual mission, that is a good design to keep them from eventually trying to keep you from reading Mein Kampf or Lady Chatterley's Lover or something. (if you're in the United States you also benefit from the first amendment...)
> It doesn't take the harmful objects out of the market, so why set this precedent?
This also strikes me as a really myopic thing to say. Do you really think that eliminating an item from the toy store shelves and relegating it to scientific supply shops is not going to effectively remove it from kids grasp? The obvious counterexample is the chemistry sets of yesteryear.
(it's worse than that: those shops won't finish the magnets in the user-friendly way that these guys did. that was their innovation.)
> What makes this ruling more egregious than any other that comes to mind is that it seems to have been made selectively and without good reason.
Again, very disingenuous. Kids were getting hurt, it's not like the CPSC was making that up. "Good reason" is obviously subjective but the important thing is that it wasn't arbitrary: accidents involving children requiring abdominal surgery are something approximately 100% of us can agree shouldn't happen, regardless of the cause.
You also seem to misunderstand the argument here. If you had read the article, you would know that even when taken out of physical stores the CPSC continued to push for a banning of the Buckyballs. So clearly this legislation isn't about eliminating it from toy stores, as that already happened and wasn't sufficient for the CPSC.
I'm very much not trying to be disingenuous, I realize children were harmed. However, if that is the simple criteria we are using to determine businesses to legislate away then the selective enforcement is even more worrying.
It's plausible that they might become overzealous, sloppy, subject to some unforeseen corruption, etc. Your previous assertion that they might begin censoring speech strikes me as rather over the top.