There's a lot I can say here, but to be terse, the money paid into (un) employment insurance is more than what is paid out normally, since some people will pay for it all their life without ever collecting, that money isn't just stored indefinitely, it's used for other things.

As a result, if a large portion of the population suddenly find themselves without work, the system will be unable to sustain itself, whether "short term" or not. All systems that rely on EI overflow funds would suddenly have a deficiency in their money flow, and considering they the people pay most of the taxes while billionaires and corporations get tax breaks so that they pay nothing, the entire social support systems would collapse quickly, as the country plunges further into debt, devaluing the countries currency.

The entire economic model is built upon things maintaining and continuing mostly as they are, pull any thread too far and the whole thing unravels.