The people who don't think this is a big deal are either lacking some empathy or don't understand how conferences work. The equivalent situation is something like being warmly invited to a wedding, which you accept. The bride and groom then spend time gushing over how great it is that you'll be there, telling everyone they know, insisting that you book tickets right away. Later, you're told you can only come to the ceremony and not the reception or party.
In short, it's hard not to feel like you just got baited and switched, even if the withdrawal is for a good reason. "But you'll still be at the ceremony!" isn't a good argument because that wasn't the original invitation, and because you're putting them in a very uncomfortable position having to decide whether to continue to go or not.
For context, I've spoken at over 100 conference events. There are very significant differences in terms of the keynote speakers and regular speakers — generally in compensation, status, time, and prominence, at least for conferences that are larger than community events. Not all of these may not be obvious to attendees, but overall it's a fairly serious snub to pull the rug out from under someone like this.
In short, it's hard not to feel like you just got baited and switched, even if the withdrawal is for a good reason. "But you'll still be at the ceremony!" isn't a good argument because that wasn't the original invitation, and because you're putting them in a very uncomfortable position having to decide whether to continue to go or not.
For context, I've spoken at over 100 conference events. There are very significant differences in terms of the keynote speakers and regular speakers — generally in compensation, status, time, and prominence, at least for conferences that are larger than community events. Not all of these may not be obvious to attendees, but overall it's a fairly serious snub to pull the rug out from under someone like this.