It's a bit of an overstatement to suggest the result of the appeals court decision renders Rule 16 a dead letter and establish discovery rules equivalent to those in civil cases (for example, you get to depose experts, pose interrogatories  and request production of a vast array of documents  in civil cases  prior to trial), but the sanction of excluding expert testimony is a very severe one and in criminal cases there are heightened due process requirements.

   Exclusion should be a last resort and never imposed except after an exacting review of the degree and nature of the failure of compliance and a balancing against the prejudice to the defendant flowing from the exclusion of the relevant evidence.

  I haven't followed this case that closely, but I suspect the trial judge  was angry with the defense for getting too cute and attempting to thwart the government's ability to prepare cross examination and rebuttal. I don't know the degree to which that was justifierd, but even if it was, sanctins on the defense and counsel short of exclusion should be be considered and only where none of the other possible  sanctions are sufficient and the prejudice to the defendant is not outweighed by the need to compel compliance should the remedy of exclusion of testimony be ordered.