The greatest trick the keynesians ever pulled, was convincing the world that some inflation is healthy, and all deflation is cause for fear.
For this reason, central banks will run interest rates down to juice more inflation....oh wait...they are already at near zero...
The greatest trick the anti-Keynesians ever pulled was selling governments on the nonsensical belief that sado-monetarism is ever good for anyone who isn't already extremely rich.
As opposed to 80-100 years of devaluation of the money that you earn, save and spend?
A stated above 'the greatest trick the Keynesians ever pulled off was making everyone fear even the slightest deflation, while convincing them that year-in, year-out inflation as not only natural, it was a good thing.
The main benficiaries of inflation are the people who get to spend the newly minted money first - because they get to use created money to buy assets at the valuations for the existing amount of circulation. By the time the inflation works it's way down the chain, your cup of coffee has jumped 50c but you haven't had a commensurate increase in income.
You can imagine the will reading "I leave my Rolex and and the remaing 40 years of my mortgage to my son/daughter"
The US dotcom bubble imploding was also not deflation.
Japan got a real estate bubble from extreme monetary expansion flooding into the economy in the 1970s and 1980s. They got a popped bubble when that fake economic party ended with monetary expansion falling to single digits in the early 1990s. The reduction in that rather massive monetary expansion forced their economy back to reality.
The US real estate bubble occurred in part for the same reason. The Fed juiced the economy after 9/11 to attempt to avoid a recession.
When reality hit, Japan shifted to accumulating vast amounts of debt to fake a better economic condition than what they really had. That overwhelming debt has continued to drown their prospects as the years go by, sapping growth potential.
You can see this same exact scenario playing out in China right now.
A bubble imploding is not deflation, just as price contraction on the CPI is not inherently deflation.
See: flat screen tv prices, computing prices, etc. The US enjoyed decades of general price stability and contraction due to vast automation and economies of scale after the civil war, none of which was deflation (monetary contraction).
Eventually the stark failure of borrow and spend 'stimulus' policies will get through. Maybe after another few decades of wasted economic opportunity and stagnation.