> Comparing the two scenarios, we found that about half of the observed decline in US social trust may stem from: i) ever more unemployment experiences, ii) ever less confidence in political institutions, and iii) a slight but systematic decrease in satisfaction with income.

https://www.sciencedirect.com/science/article/pii/S0049089X2...

I would also wager it has to do with increasing social and economic stratification and decreasing homogeneity.

> Why is that? What changed?

There is more opportunity for scams.

You didn't have ~20% of the population being old and feeble and rich until relatively recently.

In 2000, <10% of the population was seniors. It's been going up rapidly since then, and the growth rate won't slow until around 2030.

After 2030, it'll take another 30 years for the rate to increase ~7%. It only took about the last 10 years for it to go up ~10%.

Not to mention, in 2000, seniors didn't have the type of housing equity they have now (in REAL terms).

I'm not sure it was like that. Back then they had scams. Postal scams, work-at-home scams, beauty product scams, etc.

One possible different might be the internet. Allowing scammers access to so many people makes it easier to fish. There was probably an increase in scamming after the mainstream use of the telephone.