To me, saying "Bezos doesn't influence Wapo's output" is like saying, "Oculus will remain an independent entity inside Facebook." Not something I'm inclined to believe. Why should one believe that the billionaire (and new richest man in the world) at the helm of a major monopoly isn't influencing WaPo's content?
You are arguing from disbelief, but nevertheless relatively independent observers really do seem to believe that Bezos is taking a hands off role with the reporting choices of the Post:
It is possible that a well run, honest, independent newspaper is still a viable business model, if guided smartly in the online environment; maybe Bezos really just believes that? If so, then robust editorial independence would be part of the business model.
"I don't believe it" is not very convincing evidence. Oculus and the Post are not really comparable, nobody (statistically) cares how independent Oculus is. Even if you want to look at this from a purely business perspective - editorial independence is part of the product. It's also what ensures you can attract real journalists.
Some level of independence is possible. There may be contracts in place that guarantee the editorial board control over news content, and most newspaper journalists are unionized.
That's the evidence you've presented against my assertion, as neither of us would know the real answer. My links above could be perceived as control because a predominantly left wing paper is defensive of a company who runs afoul of a popular left wing issue, trust busting. It's as much about what isn't talked about as what's on the front page.
To quote you from higher in the thread, "But it seems to be in their long term interest to have a fair, balanced political system and liberal society as we have now in the US." Is buying a news paper to promote that idea not a form of activism?
I think you may misunderstand what left-wing people generally think. This quote from the above article summarizes it quite well:
Jon Leibowitz, a former Democratic chairman of the Federal Trade Commission, said the agency has a duty to challenge any deals that could end up hurting shoppers.
“Think about the Amazon business model — that’s typically bringing down prices and enhancing innovation, which is a benefit to consumers,” said Leibowitz, now a partner at the law firm Davis Polk. “But the FTC is a very professional agency, and they’re going to pay attention to any substantive concerns raised by outside parties.”
I’m not sure who you’re quoting but it’s not me. Also, you are the one making a strident assertion, you can’t really just say ‘none of us knows!’ when asked to support it.