> I just don't understand how billionaires think.

What he's really buying is power. Even your example of opera houses vs libraries accomplishes two different goals.

Opera houses are places for elites to gather and experience "culture". It means is you own a club for other rich people and create a form of soft power by controlling who gets invited to and can hang out at your club - and maybe put on some shows that everyone can buy tickets to as your "philanthropic contribution to society"

A library is more of a common use. At least in the modern day. Maybe 100 years ago libraries were similar to opera houses - mostly frequented by elite/educated and created a club for them to hang out at. Similar to donating to universities. But they're free for the public, so I'd argue this is quite a boon to common society.

But buying a media company is straight power. You are buying influence over how the public receives information. This is why Musk bought twitter. This is why Murdoch bought Fox news. This is why a billionaire conglomerate forced TikTok to sell itself to them. At this point, more money provides diminishing returns on power, so they buy influence in other ways.