1080 starts to get too narrow to work with comfortable when in portrait mode.
Uncomfortable for what? If it's too long to show a letter, you use the top/bottom above/below the page view to contain controls and stuff. The real complaint here appears to be entirely cosmetic, that people want their page to fit their bezel.
As it is, I use my 20" 4:3 monitor in portrait for the majority of single document work, then 30" in landscape for photographic and side by side layouts, and the 24" 16:10 monitor in portrait is limited almost entirely to web page viewing and almost nothing else although I do use it occasionally for document work as well.
I use my 16:10 in landscpae for everything - Word, browsing, image editing, video editing, audio editing. Currently I have a portrait browser window and Live Messenger off to the side, although for any app I work full screen. For documents I either zoom out to fit the whole page to the vertical resolution, or zoom in to see detail and scroll through the page. Sometimes with productivity software I'd appreciate a little more screen estate to not ahve to shrink and grow controls, but it's very workable and in no way a hindrance.
No Im against 16:9 monitors fullstop for PCs, the thing is 4:3 looks OK horizontal or vertical.
Until you're watching a widescreen movie or some games. Widescreen was chosen because it better matches the human field of view. 4:3 is top heavy.
Another media, you got a camera? what ratio pictures does it take? Im guessing 4:3
Pretty much every camera takes 3:2 aspect photos by default. And then the image is cropped to remove bits you don't want and create another aspect, which is exactly what you can do with a monitor. Just display the aspect you want.
Films on a PC is not a mainstream activity (most ppl use their TVs), Im one of the few that doesnt since I dont have a TV.
Films and TV are proving increasingly popular. The TV is still the prefered choice, but PCs are no longer just about creating documents and browsing web pages. Evne then, web pages are formatted with widescreen in mind, providing columns either side of the main content. If screens were narrower than web pages would need considerable changes to partition information differently. And by narrower I only mean resolution. If monitor was narrow in aspect but wide anough, like 1680 x 3000, then despite looking a little odd and requiring the reader to crane their neck, it could display a web page just fine.
And don't forget where this all comes from, that TVs have developed to a resolution that serves most purposes, hence no need to make a wider range of panels. If 1080 isn't enough vertical res for you, turn a 1920 x 1080 monitor on its side. If that's too long for your document, expand the app/window to be the right proportions. There's no need to create 1920 x 1440 4:3 monitors when the market is too small. Those really wanting more screen space have super high resolution monitors.