In the cases where I know the people very well this is especially interesting because they are incredibly nice people that told me the culture is overly focused on not making people feel bad. Coming from these people this statement was a real eye opener.
I currently work in a very "nice" culture. People from places where being nice isn't a priority have trouble with it sometimes. One thing people tell me I'm good at in this culture is delivering constructive criticism in a way that is accepted and acted on without the recipient feeling "bad." All of that said, Stripe sounds like it takes the work culture I'm in today and squares it. Many people will not be able to operate effectively in that kind of culture -- both in terms of being able to deliver criticism with the right degree of nicety and in terms of not receiving or being able to understand criticism that would help them improve their performance. This is potentially a detriment to those people and to the company.
If I were Stripe I would cover this head on. In the spirit of what's already there, I'd add something like "are you capable of performing at your best without direct feedback about areas where you can improve?"