One, what an AI-written paragraph: "While some ... remained silent ... [others] abstained from public comment." Aren't those the same thing?

Yes, but it works. The emphasis is that all of the richest were silent instead of just some, which was the case for the rest of the shareholders. We hate repeating words in general English (which is why we have such a ridiculous amount of vocabulary), so “silent” was replaced the second time.

Still awkwardly worded, though, so you might be right with the AI thing.