wage data is twisted by those earning $1mill salary now on $3mill salary.. but the other 99% of people earning $7.25 are now only earning $7.50-$10
so although the rich have 3x more to invest. average joe only has 0.3x
which with what is known as the baby boomers (population bloat after the ww2 who become adults in the 70's) now reaching retirement age. (lots of people were having more kids in the 50's-60's 'peace time')
where that extra 10% of population outside the norm will stop putting funds INTO retirement funds and instead be
taking OUT from retirement funds.. far more than normal retirement output of a community
imagine it this way 9 people put $500 a year in for 50 years($45k a decade)
but in a certain generation there are 10 people putting in $500 a year for 50 years ($50k a decade)
in the hopes what you get out at retirement is ~10years of living worth 5x more then a decade(get back what they put in)
i simplified things to exclude inflation and other variables

as you can see the generation that has extra population will impact the 'moneypot' of retirement investment companies and also national treasuries of state pensions(social security pensions)
in this scenario. for a whole decade either:
A) retiree's income for the whole community takes a cut and they get 10% less than expected
or
B) the retirement investment firms/social security are at a loss of 25000 instead of a 5000 gain to balance the pot to give retiree's what is deserved
in short..
it wont be a housing/sub-prime loan trigger this time. which they can cancel out by just zero-ing debt of zero cost to hide impact
it would be a retirement fund trigger which they cant easily zero-out as the funds are not 'credit creation' this time.. but actual peoples investments/value