That's not really irony. It's generally okay to have a self-referential asterisk in rules like; Tolerance, except for intolerance. Free will, except where it impedes that of another. Peace & good will, except where you're about to punch me in the face. Etc. When people argue inconsistency in those cases, it's usually sophistry.
That's not to defend okcupid's tactics in this case. I'm just saying that it's not really an example of hypocrisy.
It's definitely an example of hypocrisy. To put it in prison terms, OKC is pursuing punishment rather than rehabilitation. If you're really about bringing people together and love, then you should be promoting trying to change peoples' minds to make them more inclusive, not blocking them altogether. Being hateful back at them simply reinforces their beliefs, and gives them a martyrdom story to pass on to like-minded people: "they say they're for love, but declared me an enemy and wished me failure". Making enemies of demographic groups divides people, pretty much by definition.
Our most brilliant scientists have recently discovered that the word "love" has multiple overlapping definitions. Strange but true.
What about "we’ve devoted the last ten years to bringing people—all people—together"? How do you hand-wave away that comment of OKC's in a manner that still allows them to be divisive?
There is an irony that an entity that declares it is for creating love is going around declaring enemies, and wishing them failure. This clearly undermines their own message, and shows them to be of a similar us vs them hateship. There are Sides to be taken, and you don't want to be on the wrong one.
What they should have said is "we are disappointed, and would like to see Eich publicly change his opinion and make some form of recompense; we would like Eich to join us in our view"... instead of "FUCK THAT GUY".
Remember the people that picketed Fred Phelps' funeral with the sign "Sorry for your loss"? That is how you fight hate, not with more hate.