So why does Salesforce still prosper? They are just a fancy database.

Good question. Salesforce does well because they provide the application layer to the data.

The WWW in the 1990s was an explosion of data. To the casual observer, the web-browser appeared to be the internet. But it wasn't and in itself could never make money (See Netscape). The internet was the data.

The people who build the infrastructure for the WWW (Worldcom, Nortel, Cisco, etc.) found the whole enterprise to be an extremely loss-making activity. Many of them failed.

Google succeeded because it provided an application layer of search that helped people to navigate the WWW and ultimately helped people make sense of it. It helped people to connect with businesses. Selling subtle advertising along the way is what made them successful.

Facebook did the same with social media. It allowed people to connect with other people and monetized that.

Over time, as they became more dominant, the advertising got less subtle and then the income really started to flow.

Because they locked-in a ton of enterprise customers and have an army of certified consultants who build custom solutions for you.