"Customers like typical HNers might like Tarsnap the way it is, but Colin should instead market to [such and such businesses] using [lots of specific and actionable advice] because [lots of reasons explained in excruciating detail]".
HNers:
"Oh, I like Tarsnap the way it is."
Colin could spend one day and come up with something that didn't look super generic. My idea would be something dark and simple, like this: https://useiconic.com/
Then he supplemented this with: " let’s hypothetically assume it isn’t in the budget. In that case, we go to Themeforest and buy any SaaS template which isn’t totally hideous."
So don't complain that it looks identical to 100 generic free wordpress themes -- that was Patrick's point, and his actual advice was exactly what you call for: spending a day to come up with something.