A bunch of rich guys injected liquidity into the system because there was no central bank to do so.
Quite true. What you do not mention, however, is that non-fractional-reserve currencies do not have liquidity crises. If fractional reserve banking (meaning legalized embezzlement of deposits) was prohibited, as it had been in common law for most of the past two millennia, the Panic of 1907 would have been over before it started.
An economy can handle massive swings in equity indices without serious problems. But as soon as people start demanding the return of a deposit all hell breaks loose. In the current system a demand deposit isn't a deposit at all, it is a loan to the bank that a depositor (lender actually) can call at any time.
No economy deals well with callable loans on a large scale, and yet our current banking system is structured on them. We just call them demand deposits instead, even though they have nothing legally in common with deposits except the name.
If too many customers start calling their loans to the bank, the whole house of cards starts falling apart. A house of cards that can grow so big that no combination of honest monied interests can bail them out. Hence the advent of fiat currency, where the central bank can make money out of thin air (roughly speaking) so that it can keep those highly leveraged hedge funds we call banks afloat.