Dany's death yay, tyrion's speech nay
It was a great speech, sure, but having that scene pretty much spoiled Dany's death. John Snow didn't really have any other choice after hearing Tyrion reasoning so the probability was very little he would not kill her.
The surprise of Dany's death would have been much more interesting without Tyrion's speech, who basically told the audience during 5 minutes that Dany's death was necessary and incoming. I mean we all saw what she had done and were she was going and also noticed that John was aware of it all. That was enough foreshadowing and justification for our little brains.