Yea, we've been telling ourselves this and let's do more of the same for another 2 decades and completely destroy the fabric of society.
Put it the other way, if crime rates would increase hypothetically in Japan, you'd see a proportinal increase in incarcination rate. May be, that there are cultural differences and the crime rates are vastly different between Japan and USA. Disincitivization from hard-on-crime policies could be a non-linear function that we're just glossing over. Highly functional at low crime rates.
But the answer shouldn't be to throw the baby with the bath water and turn public parks into heroine shooting sites. Progressives have been doing this consistently, destroying our nation for last 3 decades of lies and misunderstandings of criminal justice system. Experiments like CHOP and CHAZ, which abandon all law & order are the epitome of the progressive dysfunction.