Cheap money is addictive. Japan has had cheap money (basically zero interest rates) for decades. It appears very difficult for them to get out of that place.
Cheap money (very low interest rates) means cheap mortgages, and in turn this means high real estate prices. So high that you produce a trap. Housing becomes an investment vehicle, and increasing rates means you are destroying savings for millions and millions of people. Millions of people who are politically active. Whatever measures someone tries to enact that result in their real estate depreciation, they'll make sure to oppose.
Raising interest rates then requires fortitude. Generally, a developed country's central bank is independent of the other branches of the government (executive, legislative, judiciary). It has so much power, that it should be recognized as the fourth branch - monetary. Being led by technocrats who, in principle, should not care about voting arithmetics, the central bank should not hesitate to raise rates when the economic stimulus is not needed anymore.
But theory is theory, and practice is practice. In real life, you may have a president who threatens the central bank governor via twitter, and the governor all of a sudden decides to cut rates instead of increasing them. And that was before Covid19.
Prediction (and not only mine): we'll be stuck with these close-to-zero or negative rates for decades to come.
That means real estate will continue to be sky-high. That kills mobility, that makes it hard for the young generation to get jobs in the main metropolitan areas.
Maybe working from home will be an antidote to that.