So here is the Question .Why would Banks big investers loan money to governments for little or no interest when they could buy land ,gold ,houses .Its sort of obvious the world economic system is going to collapse governments will nationalise everything we own to honour their bondholders .We are looking in the other direction while they are getting ready to strike.
The big investors probably already own land, gold & houses. Land, physical gold & houses can't be sold quickly whereas Govt bonds can probably be sold in seconds. Govt Bonds are probably handy if you live somewhere like Russia or China where the Govt can turn against you quickly and seize your physical assets like land/houses etc...
There's too much money floating around and nobody's quite sure what to do with it. There's a spectrum of risk from no risk to crazy risk. Govt bonds are at the lower end so some % of money always ends up there.
Another answer is that the world Central Banks don't want the cash. They already have too much of it sitting on their books. So they charge commercial banks money (negative interest rates) to take it in. They want the commercial banks to spend it somewhere else but there's too much money... so they spread it around.
The very rich have been getting richer and richer over the past 2 decades while regular people haven't seen their wealth increase at all. In countries like the UK & USA, it's actually gone down! In one story I read (that I trust), I think it said 3 American men are worth more than the combined wealth of 50% of the American population.
https://www.forbes.com/sites/noahkirsch/2017/11/09/the-3-richest-americans-hold-more-wealth-than-bottom-50-of-country-study-finds/#665098483cf8Most dramatically, it found that the country’s three richest individuals—Bill Gates, Warren Buffett and Jeff Bezos—collectively hold more wealth than the bottom 50% of the domestic population, “a total of 160 million people or 63 million American households.” Roughly a fifth of Americans “have zero or negative net worth,” the authors wrote.