35k/month in aws bills. 6k paying users. 10% upgrade rate.

That means their storage + servers per customer cost ~$.5/month. Storage per paying customer of about $5/month.

Ergo their $5/mo service has costs of $5/mo per paying user.

This isn't a failure to raise funds, it's a failure to achieve basic unit economics. And that's just cost of goods sold before you even think about acquiring new customers or paying staff.