Short of it is that random person emailed Larry Correia telling him that he should push his publisher to pressure Amazon to stop selling books by a now dead member of Al Qaeda. Larry responds by going on a rant about the first amendment.
I think it’s the proper response.
By the way, if you haven’t already read his Monster Hunter International or Grimnoir Chronicles books, I highly recommend them. Probably will never be considered high literature, but very fun reads.