1. The lifetime value is calculated out to far.
2. Earlier cohorts are usually less costly to acquire and have a higher lifetime value as the true fans. They are going to be your most loyal customers. Look at what happen to all of the prepackaged food delivery companies and whatever the company that was delivering trunks of clothes.
3. They never expected interest rates to rise and easy money to disappear.
An example would be that if Apple thought it would be just as easy to acquire the second million customers of its headset as it would be to acquire the first million at $3800.