He shouldn't be in the startup game if his circumstances means he can't perform his duties at the startup to make it successful. There are plenty of other software jobs more geared towards flexible schedules and a slower pace.
Disagree. The "startup game" is a job like any other. It's a contract between you and the business where you agree to provide a chunk of your time in exchange for monetary compensation and some extras. Its a business contract that will be terminated at the drop of a hat if some numbers on a spreadsheet don't add up right. That's not malice, or evil. That's just business. It's also why you shouldn't give your life away to it because you will regret it I assure you.