Agreed that the article's "case" is weak, though it does contain some interesting information.
Ultimately I think what happened is this:
(1) The financial world made a lot of risky bets that it didn't know were risky because they were based on mathematical models that various Experts(tm) with highfalutin Ivy League degrees told them were solid and reliable. "Mortgages are among the most reliable forms of investment, and when has there ever been a massive default across the board in individual mortgages?" etc., but expressed in mathematical form by people with 4.0 GPAs from Harvard. Nobody ever got fired for listening to such people.
(2) These investments blew up in their faces because these models were wrong. Specifically the problem with those models was the problem with all such closed-form models of open dynamical systems: by taking large positions on the basis of fixed closed-form models, they actually altered the system so as to invalidate those models. That's because dynamical living systems like economies have feedback loops. More specifically for this case: by relying upon models based on the stability of mortgages, positions were taken that made mortgages less stable such as by encouraging more sub-prime lending and by causing a housing bubble.
(3) As the crisis erupted, a massive scramble ensued to do something with huge numbers of people -- some very powerful, wealthy, and connected -- running every which way executing anything they could think of to prevent the next great depression or worse.
(4) In the confusion, those with the most political power, connections, and access to real wealth tended to prevail... as is usually the case, and in that order. In a fire with no marked exit routes those who are first to the exit and/or physically strongest will get out first too.
(5) After the crisis anyone with any kind of political agenda started to pick through the ashes to cherry pick evidence to bolster their pet thesis, implicate their pet enemy, or just sling outrage to get clicks.
Where's the mystery here?
The only "solution" is to reform the financial system so as to put systematic, open, clear safeguards in place so that next time -- and there will be a next time -- this happens, everyone knows what to do. This is why buildings usually have prominently displayed exit paths in case of fire, etc.
I'm too ignorant of high finance to know what that path should be, but here's a layman's suggestion anyway: what if under certain objectively determinable crisis conditions the fed made available a window for anyone to borrow any amount of money at some multiple of the current base rate? This would allow anyone -- from banks down to actual homeowners and businesses -- to temporarily cover themselves until people can figure out what the F is going on and things can unroll in an orderly fashion. This loan would have an escalating interest rate over a period of years, so all would be incentivized to pay it back, but it would give people time to assess the situation. Perhaps that or some version of it could work. The whole problem with these crises is that they can unroll much faster than anyone can think, leading to a lot of stupid decisions that make the crisis worse (analogous to rushing a single exit during a fire) or that result in massively unfair outcome. In some cases these might be corruption and opportunism, but in many cases I think it's just stupidity under stress. The goal of something like the aforementioned would be to "slow down time" a little.
Edit: a possibly better version would be this: in the event of a systematic financial crisis, the fed is empowered to bail out the consumer progressively. This would "trickle up" and prevent the entire financial system from collapsing, but would remove the most obvious forms of moral hazard at the top. Furthermore if the "angry liberal" version of reality is actually true and the financial elite are working tirelessly to keep the poor man down, that means they now have an incentive to do their damn job correctly and prevent a crisis from emerging in the first place.