That article is terrible and why so many investors miss so much of the market's returns.
First, currency plays and other functional reasons lead to negative yields. It's not simply paying to keep my money safe. Read this for some info
https://www.investopedia.com/terms/n/negative-bond-yield.asp.Second, yield curve inversion sometimes predicts recessions, but a couple of facts. First, it's the 2-year vs 10-year that should be evaluated, which is not currently inverted. However, even when that accurately precedes a recession, it is usually a year to a year and a half prior.
And finally, the problem with articles like this and so many other talking heads, is that he concluded the writing by giving himself a get out of jail free card. Making sure, while he's certainly suggesting the stock market is soon to crash, he left it open that all of this could be wrong and the market keeps moving ahead.
So... What's your plan moving forward?