the future can easily be far, far worse than anything seen in the past. Why would anyone believe otherwise? The future hasn't happened yet.

Could a catastrophe happen? Sure. Rampant inflation, nuclear war, another pandemic, social revolution; the possibilities are endless. Considering catastrophe when retirement planning is pointless. If such a catastrophe unfolded we’d be looking at a very different organization of society than the one we currently assume is natural. I dare say that capitalism, the system on which our retirement planning rests, might no longer exist. So, as a basis for retirement planning this line of thinking is pointless.

Where you have been helpful in thinking about retirement plans in the past is expectations for future returns on investment. I think the expectation that 8% is natural and to be expected is probably wrong. We might see flat to very low returns for decades, or might even experience a prolonged recession like Japan has for 30 years.

On the other hand, we seem to be entrenched in a period of intensified exploitation where working people are seeing flat to declining standards of living in the midst of a productivity revolution. If all those economic gains are being captured by the owners of capital then there is no reason to expect lower returns on capital going forward.

If you’re planning to live in a capitalist society for the rest of your life then a reasonable set of assumptions would be lower returns that historically expected to more of the same. Anything else is a bet on the end of capitalism, and you don’t survive that as a holder of capital no batter how good your assumptions are.