Because if they priced the company more reasonably many later stage investors would stand to lose money. So they’ve backed themselves into a corner of having to go public at a $1T plus valuation just so some later stage investors don’t realize a big loss.
Their last investment round in May had them valued at 965B. And the company has grown a lot since then, those investors obviously expect a profit
From where? There may be some profit but I don’t think it’s gonna be anywhere near what they are expecting and the same goes for OpenAI.