Everyone sent into space was for a political reason. Whether or not you think it's a stupid-ass reason is more of a reflection on yourself than the message.
In this case the craft was not ready, it seemed to be widely known that the person who took that spot would die. I think that is an important contrast compared to "everyone sent into space"
Sure, in the case of Komarov. But that's not what we're talking about in this comment thread - we're talking about the inclusion of a random tweet about Mike Pence that could have been left out without changing the message at all.