Just as an anecdote: I certainly don't laugh at the Tarsnap website, but it immediately turns me away as a potential customer. The instant gut feeling is "OK, this is a product made by someone who laughs at UI design. They didn't even try. The product will probably be a pain to learn."

It's most likely not an accurate description of Tarsnap, but its's a strong enough first impression that I'll immediately close the tab.

And that's a shame, a mutual loss for Tarsnap and any potential customers. Tarsnap pops up on Hacker News quite a bit, so it probably is much better than the impression it gives.

Design certainly isn't a binary choice between adopting fads and abandoning aesthetics completely. The overused styles are overused because they are viable first steps towards a decent design. The cop-out alternative--taking no step at all--isn't better.