If the "many people" are people
here (who have bashed for years about anything bigger than 3.5" until Apple rolled out (and thus blessed) 4" as the (now) perfect size-), as soon as Apple rolls out a >4" phone and bless it as the new perfect, these people will almost all fall right in line: "shut up and take my money", "how did we ever get by with those puny screens?", "I'm already in line", etc.
The "many people"
here want whatever they think Apple wants them to want. I think Apple could roll out a 10" phone and this crowd would go head over heels: "who needs pants anyway?", "my phone is bigger than your phone", "can't wait for the 12" pro model", and so on. Right now, it's just split because most want to hedge their stances (too many rumors pointing toward 4" no longer being "perfect" so we bash bigger screens less and sling phrases like "wait & see").
If Apple rolls out a bigger screen in either size, lots of the remaining bashers will flip overnight to "I'm already in line", "once I actually got to see one
" and so on. Shortly, thereafter, we'll be bashing other company phones with smaller (including 3.5" and 4" screens) and larger screens than the new (third and maybe fourth incarnation) of "perfect" so sayeth the Apple.