Yes, I agree its a bit aggressive. Ultimately it was human nature... spreadsheets don't cause apocalyptic financial crises, overzealous capitalists with spreadsheets cause apocalyptic financial crises!
The author was (is?) a recruiter for quants and financial developers so he certainly had a unique perspective.
Is it just me, or does the financial system seem to be designed in precisely the opposite way of how we try to design good software? One huge intertwined web, where one small thing indirectly affects thousands of other things. Its seems to be the equivalent of a "big ball of mud" type piece of software.
That's a rather aggressive phrasing of what the article says, that many of the calculations involved in the credit crunch were done in Excel/VBA.