The mention of FSB is downvoted is because it was near-immediately clear that this was not the cause. It's total amateurs doing wild speculation for who knows what reason - some stupid upvotes on a website or because it makes their life more exciting to feel like they're whistle-blowing some international conspiracy?

This is roughly on par with every celebrity death over the last 4-5 years being followed by idiots commenting "vaxxed?!"