It wasn’t unreasonable to trust Stack Overflow when it first launched
One of the things that the Stack Overflow brouhaha demonstrates is that it doesn’t matter if a service was founded by people trusted by the community (Atwood and Spolsky) and was broadly community-led. If it’s a VC-funded startup, they will sell out their users at some point.
People forget that “by developers, for developers” was a big part of Stackoverflow’s initial pitch. It was founded by people who most of the community implicitly trusted. They said all the right things. But as soon as they took VC-funding it was just a matter of time.
I think we know better now than to trust something like a VC-funded community site, but remember that StackOverflow was founded in 2008 at the tail-end of the Web 2.0 funding bubble. Getting community sites funded by VCs (or VC-adjacent angel investors) was the style of the time.