And, their product have worked correctly for decades.

So if you have a lot of money and don't want to take any risk you go the oracle route. It's not the best product today, but you won't have any surprise, except cost, that you can justify because it's oracle.

Which is the same as using a tank to go grocery shopping because you're afraid of an accident on the way. You need everything in house to support a thank, special garage, specifically trained crew, specific fuel...

And it's way harder to drive than a civic.

Precisely this. They prey on outsource-happy big orgs that have 1 million different SaaS all tied together by scotch tape (because their IT dept. is also outsourced)

The whole medical industries business model is that they create so much compliance regulation that you need every compliance product under the sun to comply with them, thereby you can keep out competition.

Non-tech companies have bigger fish to fry in cost optimization than IT infrastructure.

For example, nobody buying, insuring and operating supertankers will care that much about Oracle licensing or even renewing a mainframe contract.

I have a theory that being cash-rich creates an atmosphere of technological cluelessness, or more specifically weaponized incompetence. A cash-rich company attracts sociopathic executives, who are focused on the prestige of working at a top company. These executives display a unified front outwardly, but internally they are all stabbing each other in the back constantly. And any executive who champions in-house software is just giving other executives ammunition whenever said software has the smallest bug.