I hear this argument come up a lot and frankly it's just misleading to even bring it up. When a company controls an open source project, the project follows their vision–regardless of whether there are a couple other groups with slightly-more-than-nominal contributions. Ask yourself whether any one group could prevent a commit from going in that Google corporate had decided they wanted in Chromium–the answer is of course no. It'd be like saying Apple doesn't have essentially full control over WebKit's direction, even though this page lists a bunch of people who aren't from Apple: https://webkit.org/team/
Free and Open-Source projects, unlike IE, can be forked anytime by just anyone or any other organization. There is nothing preventing anyone to go ahead and rework Chromium for their own needs - and that's what happening in practice already with Brave, Edge, etc...
The day that people/organizations are upset with the direction Google takes with Chromium is the day where a real fork will start existing and being actively developed by a larger community.
For this I would propose a litmus test for forkability of a project. If the original parent company disappeared would the fork be able to sustain its development and maintenance alone?
For current chromium forks (and also for firefox forks) the answer is no.
The only fork that would have the resources would be from microsoft, but it would be a huge, expensive, and non-trivial task.
> If the original parent company disappeared would the fork be able to sustain its development and maintenance alone?
The counterexample is the Linux kernel. No single company can actually sustain its development, so in practice many companies work on it together with an agreed governance to direct where things go.
Indeed Linux is not forkable in practice, most current forks rely on the cooperation and coordination of the linux foundation at least partially.
For chrome as long as google exist I don't really see an industry consortium to invest in marginal improvements (considering also how the interested industry partners are likely heavy google customers)