Yeah, but this is Larry Ellison we're talking about. Do you want to trust his idea of "good for shareholders"?
Absolutely. I have no doubt Larry will do what is good for shareholders.
I also have no doubt that Larry will not do what is good for consumers, but that's a separate question.
The theory is good, but in practise it doesn't always work out that way.
As an example, take IBM. In IT circles they're very well known - for ~10+ years now - as an incompetent organisation, with an aggressive sales force targeting high level (non-technical) execs.
Their only real interest in being scoring short term sales wins, but their ability to deliver results for any useful length of time rarely lines up.
In theory, IBM should be having trouble closing sales these days. That's the equivalent of "If Tesla cars aren't safe for the people inside, people won't buy them".
However, that doesn't seem to be the case.
And with IBM, when things go badly wrong (very common), IBM just breaks out the lawyers and attempts to shift blame. eg "it's the customers fault / hackers did it / competitor did it" (etc)
Telsla could unfortunately drive down the same dark road (for their customers).
Having Ellison anywhere involved is really not a good sign. :(
And of course as you mention there is the possibility that Ellison is irrational.
Regarding irrationality -- see e.g. this[0] Shamus Young post about the video game industry. IMO, this general sort of irrationality is everywhere. Businesses in general tend to be irrational because they're run by suits, whose primary motivation is not actually accumulating money for the business but rather prestige for themselves, which you get by doing business-y things, regardless of whether those actually make money. For all his reputed greed, that's how I actually expect Larry Ellison to act.