What really happens to somewhat affluent people, business CEOs, influencers that express negative opinions about CN gov?
In other countries, there is a lot of unexpected "suicides", and people simply cease to exist, but in CN they usually disappear for some time and when they "reappear" again, are not interfering, commenting or criticizing anymore in any way... What actually happens in that "transition" period?
I'm genuinely curious, please provide some sources if there are some, or if this was answered somewhere else already.
I don't think you're going to find much concrete evidence on what China does in secret to disappeared billionaires. It probably varies. Some combination of prison, house arrest and re-education are certainly likely. Most guesses probably say more about the poster's thoughts on China than about China itself.
Incidentally, I desperately wish we could just shove musk in a secret prison for a few months. The amount of power he has is itself a threat to democracy, even if he wasn't personally a dangerous lunatic.
Probably ask nicely, then just threaten to take away their money and source of income if they refuse. Slavery in prison is probably the last resource. Just like in the US.