It's quite simple really. You haven't seen the numbers the investors have seen. I used to work in the private capital markets and it was awesome to be privvy to information that gave you more insight than can be gleaned from the outside.
Like the numbers investors saw for Snap before it’s IPO and it’s not doing so well right now. This 120B valuation doesn’t make sense regardless of the numbers. Especially considering they just did a bond sale with an 8% coupon. What company worth 120B sales bonds with an 8% coupon? Absurd tech bubble with ridiculously valued “unicorns”
8% on an 8 year coupon for $1.5B sounds like a heck of a deal for a growth company relative to raising another round. That's just around $2.8B paid back 8 years from now. If the company modestly triples from their current value over 8 years, that's a $1.7B savings.