From 1929, central bankers learnt that liquidity can be a terrifying disease in an economy, 2008 showed that printing helps and here they go with their newly learned tool trying to fix all problems. Now they have to figure out that if you only inject that liquidity from the top, the inflation appears in certain kind of assets (mostly financial) and has a hard time reaching the rest of the economy, causing ever-rising inequality.
I think a more refined approach will be developed at some point, where they will start using two levers to steer the function of the economy. Money printing from below via UBI and regulating the inflation of day-to-day assets and money-printing from above and regulating the inflation of financial assets. This could allow finer control balancing target inflation rates of different assets and preventing rising inequality to tear down society.