Stack Overflow (and the Exchange sites) are a technology platform and a community. The community is the people who use and curate the site and their shared values. These work together to produce a superior outcome to other Q&A sites which appear to rely on gamification alone. SO the company is in complete control over the platform but not the community though it has previously enjoyed good relations with the community as the values were aligned. Community feedback was appreciated and acted upon.
The problem is that now SO is trying to monetize the values are changing. A focus on quality is being replaced by growth; a clean and stable interface is being disrupted to suit marketing metrics; values driven advertising is being replaced by the Wild West from the rest of the web. The company is leveraging its control over the platform to try to control the community and sees any pushback as a problem with the community ("unwelcoming").
This is leading to a fracturing of the core essence of the site. The company and the community see the future through different lenses which are mutually incompatible.