I thought sensible Jews had dismissed the "one-state" idea a long time ago. You can't share a society, a social compact, with people whose fondest dream is to slit your throat in the night.
Since absorbing Gaza isn’t a consideration to anyone, most people don’t think it would result in a palestinian majority, though the future demographics could be problematical I suppose. Actually there is support for a one state solution, mostly on the Israeli right. Things like the conditions for citizenship could be problematic. Arabs living in East Jerusalem have been eligible for citizenship since the 1967 war. It’s my understanding only a minority have taken up the offer, which is still open. I haven’t read Caroline’s book so I don’t want to mischaracterize what she’s proposing, but there have been proposals for partial annexation. I recall one from a decade or so that would have created a self governing area, but with Arabs having Jordanian citizenship, which obviously wouldn’t be practical, Jordan likely refusing. Or a transitional area, with the benefits of citizenship right to vote postponed to a future date when stability has been established. Personally I’d be skeptical of anything but a partial annexation, but I’m not an Israeli and don’t have to live with the results. There have also been suggestions that Arabs who wish would be financially rewarded to voluntarily relocate, also a likely non starter since no Arab state is going to take them. Obviously the two state concept isn’t workable as long as terrorists, quiet for now, run the West Bank.