When there is a perfectly good objective argument to be made (in this case, that undeletable reminders is a bad user experience), I do think an appeal to emotion is ineffective if not fallacious.
In this case, the particular emotional appeal seems either insincere or unreasonable. Are people who have bad or deceased fathers offended by the very notion of Father's Day and the marketing around it? I doubt it, but even if they are, I think it would be entirely unreasonable, and rare enough for Google to risk or ignore.
Remember, anyone can choose at any time to be offended by anything, whether or not other people would consider them reasonable. People can also feign being offended to attempt to bring attention and credibility to an otherwise legitimate argument. Anyone who publishes any text on the Internet is liable to have someone claim the text to be offensive. I don't think any reasonable person would see this reminder and think that Google was mockingly telling them to call their abusive or dead father.
That's the difference between posting something in a space people view as public and a space people view as their own personal area. People have much more of a right to be offended about the later. You're offering your users a space to call their own, anything you put in there that offends any of them is an intrusion and leads the user to realize that the control of that space is entirely up to you and not them. When you've offered that space to them and they find out your offer is not what they thought it is, it is understandable they get annoyed.
The reason it's important to talk about the emotions is that the emotional calculations change when the space or message is a personal one as opposed to a public one. It's the difference between someone coming up to you on the bus and asking you if you've called your father and a poster on the side of the bus asking if you've called your father. When you put your message in someone's personal space, you don't get to just say "eh, it's probably only a small fraction" because you're specifically communicating with specific people.
It is important to understand the emotional components of software.
I don't buy that Gmail is or is supposed to be a personal area. There are prominent ads, and Google frequently sends out messages to everyone's Gmail about new Labs features and such. Sure, your Gmail is more personal than, say, the cnn.com homepage, but it's still pretty clear that mass messages aren't off the table.
> Are people who have bad or deceased fathers offended
> by the very notion of Father's Day and the marketing
> around it?
There's a difference between Bob Barker saying "Remember to have your pets spayed or neutered" and Bob Barker coming to your house and saying, "Hey, asshole! Spay your dog already!" You are arguing that there is no difference. You seem to base it on the idea that if someone feels offended by Bob Barker talking at them specifically, then they need to be offended by Bob Barker broadcasting to a large group of people in general.
In the same way, the general idea of Father's Day is different than talking specifically to someone about their father. At that point, it is no longer impersonal (or easily dismissed as, "They are just talking to other people / people with happy father memories").
It's pretty clear that Google doesn't know your father or your family situation, so their little reminder is a lot different that Bob Barker actually showing up at your house. Also, I don't get this assumption that your GMail is your own personal space. There are ads on every single page, and Google has a long history of sending out blanketed messages (e.g. new Labs features).
> It's pretty clear that Google doesn't know your father
> or your family situation, so their little reminder is
> a lot different that Bob Barker actually showing up at
> your house.
Bob Barker showing up on your doorstep does not imply that he knows anything about you personally, other than that your dog isn't spayed. Google doesn't necessarily know anything about you personally, other than the fact that you have (or had) a dad.
> Also, I don't get this assumption that your GMail is your
> own personal space.
* Are you suggesting that it's a public space?
* You may not 'own' it, but that doesn't mean there isn't an expectation of it being a semi-private space. You are leasing the use of your Gmail page from Google at the price of the ads being there. What if your landlord went door-to-door in your apartment complex telling everyone, "Call your father!" When your landlord shows up at your door, you don't know that he's going around to everyone. How would you not see that as personal?
* "Call your father" is a command, which is a lot more personal than "Father's day is coming up, you might want to call your father for free using our service!"
> There are ads on every single page
Do you not own your (purchased or gifted) copy of (e.g.) a newspaper? There are ads on every page.
> Google has a long history of sending out blanketed messages
> (e.g. new Labs features).
Most normal people don't get this, or just ignore them thinking that they are spam. And in reality your email inbox designed for sending/receiving messages. Your task list isn't. Do you expect the ability of others to automatically add things to your own personal TODO list? Even sending calendar invites through email usually requires confirmation before accepting them.
You're being extremely inconsistent here. "Public space" is not the opposite of "personal space." I'm saying that your Gmail page is not personal, because Google has always placed advertisements and other messages on it. It is unreasonable to single out this Father's Day reminder and claim that you didn't expect mass messages to be placed on your Gmail.
Your newspaper analogy is the most inconsistent yet. Of course you own your copy of a newspaper, and of course there are ads. But a newspaper is not your "personal space," and in fact, I'm sure most newspapers had Father's Day ads.