Why would you think that? You think pension funds and governments didn't invest this time? Because that's the problem, governments either investing everyone's money directly (to fund their own loans and expenditures, or should I say fund their own expenses using pension money without admitting that's what they're doing to pensioners) or indirectly force investments (you'll find pension funds worldwide are legally only allowed to invest in loans to the government and specific things the government allows (like politicians' charities). "For safety", of course, no other motivations there)

We can check if governments went back to their own tricks or not after 2008. What were the interest rates after 2008? Quick check ... yep, they went back to the old tricks.

When "shit hits the fan". Either governments really cut spending, leave pensioners without income and see their new loan interest spike to 10%+ (if they're lucky) ...

OR they do a massive cash injection saving the banks, and increase spending.

Which would you chose? It doesn't even matter. If you were the government and chose the first option, you would quickly find suddenly everyone across the political spectrum uniting to depose you. A decent chunk of people would literally not have any other choice but to do that.

(of course, as per usual governments aren't behaving "correctly" according to economic theory. If you take the old "government as spender of last resort" governments should have radically cut spending in the last 10 years, because there was no need for extra spending. If you take the new "government invests pensions", then of course government spending needs to be investment. In other words, governments only allowed to spend like a normal investor, expecting and demanding a return. Ie. no social spending increases. In practice governments increased spending at any cost, and so we're in trouble again)

Oh and should I mention that for any other entity investing pension money in loans to yourself is a very unique thing in law. It is THE ONLY financial crime where corporate structures do not protect management. You're the worldwide president of ExxonMobil? Doesn't matter. You do with employee pension money what government does with it? (ie. loan it to yourself, in this case ExxonMobil). You go to jail. Directly and long-term. In America. In Spain. In Japan. In fucking Vatican city.