Sincere question, been studying lots of OSS commercial licensing and always wonder what works in which context
Yes, it's a good-faith license. The license doesn't even apply to the OSS version (only prebuilt binaries).
The bet is that super fans will pay for it in the early days and, as it gets adopted by larger companies, they will pay in order to comply with the legalities of commercial use. So far, it's working! The largest company so far is 34 seats, with a couple more in the pipe!
It makes good sense because companies actually have an absurd amount of liability to you if they violate your agreement.
You can be an Oracle and audit your customers and develop that adversarial relationship. The idea is that that sort of thing makes you rot in the long run.
They have a lot of inerita, but that's it. If you're in Greenfield development, there is a close to 0% chance you will choose Oracle as your RDBMS.
Um, oops.
But that's A) me personally and B) me in Cloud/Startup type companies, so of course we don't got with Oracle.
But like you mentioned, inertia. So my previous gigs that were large multi-national of course were all Oracle. And they were all huge and had zero reason to not just buy the Oracle tax. Which is why Oracle is going strong.
Despite all the rage, Oracle can still survive quite some time on running boring things like I don't know, many large banks and other boring old businesses. Which of those is really gonna go "AWS Aurora MySQL" when the have had an in-house "Oracle Exadata" run their entire business operation "just fine" for longer than those Cloud providers have even be around?