Both Blair and Brown were in part responsible for the financial crisis.
From around 2000 and the dot com bust responsible voices in the financial world were saying that credit was being allowed to expand to fast and too far. Do you remember all those 'Self-certified mortgages' where people lied about their income and their figures were not checked, Brokers offering multiples of 6 x income? All those fianancial 'products' we were advised to invest in that nobody understood?
Credit control was in the hands of the government. If they had tightened financial controls, used the usual instruments for reining in bank lending, we would have been affected by the financial crisis but nowhere near as badly as we were. Much of the responsibility lay with Blair and Brown, but especially Brown, Mr 'Prudence' who in the end proved as incompetent as nearly every Labour Chancellor I can remember.
I have little time for the Conservative party, but my lifetime memories are of Labour getting the country into a financial mess, the Conservative's cutting and taxing to sort it out then handing it back to Labour to ruin again, in an infinite circle. Austerity would never have been so bad had Blair and Brown not spent so much time brown-nosing the Russian oligarchs and rich US bankers and politicians. - money, money, money
If the Labour party abhorred those two so, why didn't they chuck them out of leadership ad stop giving them standing ovations at party comferences.