While I see the points made in the article and while a 60/40 portfolio isn't really for me, and that I would agree with that for myself...

It surprises me how naive people have become in thinking that bonds and equities will continue to be closely correlated. eg



Perhaps it's just their lack of experience and lack of number of years investing. Or they haven't lived through different types of crises crashes. Another one:




A very short sighted view in my opinion, particularly if someone is living off their portfolio income. In a crisis some bonds in your portfolio will more likely safeguard your capital and have a higher yield. They make the assumption interest rates and inflation rates will continue to gradually increase. Yes if that happens then bonds will have been a waste. But what if that isn't what happens? What if there's another (unexpected) crash? Economics 101 economy tanks, interest yields fall, bonds prices go up. Meanwhile depending on the causes equities could very well tank along with the economy, profits down, companies fail, dividends cut etc.

While their analysis may indeed be valid for the last 10 years post crisis. There are at least two big flaws in this:
1) The last 10 years has been full of massive distortions of monetary policy, QE and the likes. These have distorted correlations enormously
2) Post crisis analysis. Yes it's exactly that. For someone living off their portfolio for the next few decades, they really need a crisis or three in their analysis to understand where bonds come in. Their time frame is too short. Crises also come in different forms. eg just talking interest rate and inflation movements overlooks credit factors, liquidity risk etc

I say this as someone who for the first couple of decades of investing saw bonds as pointless, even thru the first crisis or so. And that's despite all my formal studying and reading on the subject. I used to be 95% + equities for many years. Looking back thru history though I saw how I could have improved my own portfolios. Particularly with a focus on living off them, rather than wealth creation. 2008 was a major year for seeing that. So I would say ignore bonds at your peril and the fact they can behave differently in severe market conditions. The people who write these sort of articles (and they seem to becoming more and more), remind me of myself in earlier years, with less experience

Would also have been nice if they has shown a 100% equity and 100% bond portfolio just for completeness. Of the 5 choices they gave I would have said 80/20 without reading the article, and wouldn't have touched the 60/40. The question for me is whether 10% to 20% bonds in there might be worthwhile.

Throwing in a multi asset comparison would also have been interesting. For me I long term I aim for around 75%-90% equities, some bonds and some other assets, to smooth thru the crises a bit better