https://news.crunchbase.com/news/softbank-dealt-in-tenth-of-...
It could trivially collapse the VC market as companies are largely failing to IPO, and depending on how it's leveraged (I do not know nearly enough details) it could absolutely have serious economic shockwaves throughout the world.
> I can't imagine their failure hurting market sentiment overall.
I don't see why it would be any different than 20 years ago and the dot com bubble. Everybody says this time it's different, yet the overwhelming majority of tech companies IPOing are hemorrhaging money. Look at Uber - losing billions of dollars per year with no end in sight and their stock continues to decline. And of course Uber was a Softbank investment.