A 50% unemployment rate seems highly unrealistic now or even in the not so distant future. However, let's assume this did happen. It would be totally ugly and insane to see, the world would probably look like Mad Max.
Depends on the nation, would you be shocked to learn Ukraine has that? I do not know if they do, but if they do that would make sense because they are in a war, USA may not, of course it looks like a distant future thing or at least unrealistic for the time being, but even that wouldn't shock me if it happened 10+ years from now because we are not growing big enough to hire everyone, and the population keeps on growing, meaning it is going to cause a lot of people to be unemployed eventually.
The amount of people we have is growing, but the amount of money is still stuck with a few thousand people at most, meaning we are creating more poor people every single day.