Those are not criticisms of 7" screens, but criticisms about the absurdity of promoting the idea that people would rent a small video player for entertainment on an expensive cruise, where activities, tours and large screen movies abound. If that were someone's business concept, I'd say it would fail miserably.
For situations like flights, train rides, etc. when one is confined with few options, I think a 7" screen is certainly adequate and have never said anything to the contrary. Interesing how you twisted the meaning of my words.
I'm booked to go on my first cruise in January and can assure you that I have no intention of sitting around watching a small video player (edit: even during "sea days").
