This is an unusual step for a Venture-backed company. If David Byttow's positioning is accurate, the company is ceasing trading because the reality of an anonymous network was not what he'd hoped; the financials were not the driver behind the decision.
According to the FT, the company has raised $35M so it's probable they do still have plenty in the bank and I guess their investors would prefer to have some money back rather than none. Nonetheless, it seems a bit rough on the employees and their many dependants to simply shrug and walk away.
I believe in honest, open communication and creative expression, and anonymity is a great device to achieve it. But it’s also the ultimate double-edged sword, which must be wielded with great respect and care.