The claim itself seems to be the more misleading part of this, though I can understand where it comes from. The Guardian, where this article is from, is mostly reliable, but can sometimes favor the Left. Normally this doesn't hurt its objectivity enough to really skew the facts, but this article sometimes leaves out some small details that can explain Bezos's intentions.
An article about this same situation from The Hill, a news source that I've found to be very objective, sheds some light on what happened. As the article states, Bezos didn't necessarily abuse his power to favor a certain candidate. The Guardian goes on about how he didn't endorse Harris, but leaves out the fact that he didn't endorse Trump either. Something that The Hill stated, which wasn't in the article from The Guardian, was that he "abstained from endorsing a presidential candidate" as a whole. Officials from Bezos's company would later go on to attend a meeting with Trump, but with the context that Bezos never formally endorsed Trump, it was moreso a decision of his business's success instead of a way to skew the election.
The Hill's article:
https://thehill.com/homenews/media/4954196-bezos-decision-post-endorsement/