That's a bit glib considering you also need to deal with funding, investor relations, market fit, and all kinds of other issues that have a lot more impact on longevity than developer salary.
It also ignores the fact that markets are structured to reward cheap and greedy behaviour and C-suite narcissism, and to punish - or at least get in the way of - bottom-up worker democracy and other more fluid and less myth-of-the-holy-CEO management structures.
As for Amazon - the company can clearly afford to treat its workers better. The actual effect on profitability is likely to be positive, not negative, because better people will stay for longer, less churn means more stability and less random technical debt for new hires, and better publicity makes it easier to keep customers than lose them.
Bezos seems to think the tradeoffs are fine as they are. I think he's wrong about that. Amazon's model is quite brittle, and it's open to any number of competitive attacks. And Bezos has made some very poor decisions (phone, etc.)
Amazon will be fine in the short to medium term, but I'll be surprised if its business model isn't seriously disrupted by competition within less than a decade.
IMO treating workers better would make the company more creative and resilient, not less - and probably more profitable too.
