Everywhere you say? I don't know where you go online but only information I ever heard about him was here.
Comparing his apologies to 9/11? Because death of people is equivalent to buying a lot of amiibos. Honestly you can't even compare an important event to a guy that buys toys and sell it just because they hate it.
Also you shouldn't care on what other people think of him and asking for an amiibo. Just ignore them. It doesn't effect you anyway.
YouTube and Tumblr have a lot of talk about him and I visit those sites a lot, so yeah, I see him everywhere I go on those sites. The Rosalina tag on Tumblr is 99% talk about him right now. It goes without saying that an actual Rosalina fan will see stuff about this situation more than someone who isn't.
And yes, you can compare them - the principle idea of what's happening is the same as the hypothetical, alternate 9/11 scenario I described (as 9/11 did not actually happen in the way I described) - person does bad thing and tries to avert the negative consequences by saying "it was a joke and I'm sorry", but does not do anything to fix or make up for the problem. I just provided an extreme example to drive the point home.
And I am perfectly entitled to voice my thoughts on something even if it doesn't effect me. I have my Rosalina Amiibo secured and will do the same for other Amiibos, but I still have every right to have a problem with what he's doing and update people on the current state of the situation (since most people were under the assumption that he didn't purchase any Amiibos in bulk due to his most recent video, but he's come out saying otherwise, so I'm updating people on that, and prompting them to be quick about it if they want to get a Rosalina Amiibo).
At least he isn't destroying them
Honestly? That would be better if he did. At least then, some people who aren't privy to the situation won't spend $100 on a $13 figure just because he bought up tons of them to force people into that situation. Those people will probably get their figures regardless, since they will be restocked.