Figuratively speaking, we're telling them, since we're saying it loudly in public. You bet they know people are saying it. They might even peek in - we know some of their friends (arguably friends) who do, and Musk is among other things famous for being a bit of a social media addict.

Rich people's bubbles are thick, and their "outside-the-bubble" communication tends to be write-only. I highly doubt Zucc or Musk spends any time at all on places like HN or Reddit, and their comms on their respective social media platforms tend to be broadcast sending/writing and not reading comments or feedback. They rely on the sycophants in their orbit to give them the summarized, sanitized, positive feedback, and downplay/hide the negative.

We know Musk spends time on X. We also know he reads as well as writes, because he often replies to random things.

But even for a slightly wiser billionaire who does what you suggest - they wouldn't do that unless they knew they would get public hate, and were bothered by it. You don't have a thick bubble unless you understand that you need it.