[wpietri]

It is still true. The lean analysis of waste splits things into "necessary waste" and "pure waste". For a particular place and moment in time, there will be some waste that you can't remove without harming production significantly. That's necessary waste. The goal in the long term is to reduce total waste by finding ways to make some bit of necessary waste unnecessary.

It's true that pandemic supply chain issues have change the level of necessary waste in a lot of supply chains. But that doesn't make inventory good. Often production halts not due to everything being missing, but a shortfall of just one input. A company might mistakenly react by stock up on everything, but that still won't solve the shortfall of the critical component.

So should the just stock up on the critical component? Go get a year's backlog of that? If everybody does that, that will cause a shortfall all on its own, as when everybody did panic buying of toilet paper in 2020. And then when supply chains straighten out, then the stockpile is back to being unnecessary waste. So I don't think there are any simple answers there.