Too big to fail also was meant to communicate the vast amount of effort, time, and money that would be involved in rebuilding the financial infrastructure if indeed it had collapse, not to mention the immense short term pain and suffering that would occur in the interim.

A SendGrid sized void could be filled in a matter of weeks to months by teams of highly motivated engineers looking to fill a market gap. The cost of starting up there is virtually nonzero (compared to say, starting a bank), and the regulatory burden is virtually nonzero (Email regulations are arguably some of the most clear and concise).

All that to say, drawing a comparison with the "too big to fail" bailout of major US lenders is, frankly, silly.