To be honest, i don't really see why this address would be special...
It would take a very short time to generate several of these addresses, then make sure there's only one UTXO left funding said address with a predefined amount of sat's.
In this case t's not about the difficulty (at least not for me) but I do think it has some kind of a story to it.
It might be more interesting to find the vanity addresses that actually belonged to certain people, or that were used in certain events?
If you know of any, please share them. That's one of the reasons I started this thread: addresses with some kind of story attached to them, hell they don't have to be vanity addresses at all as long as they come with a good story attached to them!