It's easier to imagine that Microsoft isn't going to monkey with your private data, and that they in all likelihood have a 24x7 security team actively prowling

It's easier to imagine that Microsoft isn't going to monkey with your private data, and that they in all likelihood have a 24x7 security team actively prowling around looking for intruders. But a fly-by-night outfit has no reputation at stake and probably has no ability to realize that their whole junk has been pwned by Chinese intelligence or whomever.