Digitalization of finance since 1970s thanks to computers made it very easy to create wealth from thin air. Popping up 'derivatives' and juggling numbers inside fast-trading computers of major banks and investment firms. This also literally stopped investment in real world - why invest in actual physical goods and services and go through all that effort to expect some percentage of returns in a decade while you can just dump the money into investment tools and they can bring in money from nothing...