I sympathize with your view and certainly would be one of the folks who are done when Sony (and let's face it, MS already has gone there) inevitably does it.
I'm not so sure, however, Sony would see the revenue drop off you think would happen. Content is king, after all, and Sony is also sitting at 75/25 digital-physical sales, with digital growing. At some point (if we're not already there), that physical revenue gap can easily be taken care of by selling on PC or raising subscription prices on your base audience.
And where else would gamers go, anyways, for AAA single-player titles? Sony pretty much owns the genre and with Xbox basically done (come on, no one actually believes Spencer anymore, do they? The man is a corp. shill), the platform market will likely consolidate one more step with Sony's next console stripping off a good number of Xbox gamers.
I just don't think core gamer and physical media gamer overlap anywhere near as much as folks think they do; add to this the fact that the number is getting smaller by the day as older gamers age out or "give in," and I think there is just no real scenario where dropping discs harms your revenue growth.
Folks also like to point out that there are customers who don't have good internet. Well, sad to say I don't think Sony (and def. MS) give two s$#ts about those customers. They're happy to leave them behind because whatever money they lose there can easily be made up from those with solid internet connections.