Actually Occam's razor would say that WaPo will naturally have a bias towards Bezos. That is the simplest/purest answer.

The simplest view is that Bezos owns WaPo and therefore he will have undue influence over WaPo.

I don't ever envision WaPo going on a anti-Bezo rant like they do with Trump/et al.

Also, occam's razor says Bezos bought WaPo for his own benefit. Nothing wrong with it. But people are so eager to tech gurus the benefit of the doubt or project some "saintly" traits to them.