Here in this thread we'll cover every phone except maybe those funny things with a wheel. Cellphones, DECT phones, satellite phones... Slightly outdated trunking radio phones...
Military radiophones. NASA/ISS "phones". Skype-like apps... 

So, what sort of a phone have you had/do you have? Brand?

Perhaps the JPEG quality or resolution defaults to low (the output is only 1.6 MB)

Resolution is set to 16:9 (16Mpix). The only alternative is 4:3 (13Mpix).

This is kind of odd because in Android apps the max res is 5984 x 339x (187:106, 20.3 MP).

There are no JPEG quality settings in the Sailfish photo app, nor an option for RAW.

A lack of settings can certainly be defended to some degree. Is there any point to being able to select 160 x 120? Or really almost any of the lower settings? Presumably those modes are there to save apps like Skype some processing power when they have to limit the resolution to something like 1280 x 720 for bandwidth reasons but they really have no place in photos. My SE T630 took pictures in 320x200 (or some such). I haven't the slightest desire to replicate that. Curious sidenote, my Zenfone 2 offers 2M as the lowest option, which is basically the smallest resolution that isn't completely hopeless.^[1]

By contrast, there's certainly something to be said for recording in 720p or perhaps even lower if you don't need higher quality video.

Anyway, conclusion being that regardless whether you use RAW, the results show that you require an Android photo app because the stock Sailfish one is worthless. Luckily Open Camera and FreeDCam are pretty decent, probably others as well.

¹ A good camera can do quite well with 4 MP, for example. I've got an old Konica Minolta 6 MP DSLR here; excellent quality. The difference is that all 6 megapixels are stock full of information, while the "20" megapixels on my XA2 are largely noise.↵

The Linux (Ubuntu) phone Librem 5 is sold with "a compatible 30-inch monitor, keyboard, and mouse," implying that it is designed as a potential desktop replacement https://shop.puri.sm/shop/librem-5-30-inch-kit/

If the monitor, keyboard, and mouse all work while the phone is charging at the same time, it surely serves its purpose. I have managed to connect my Galaxy Note 4 to external monitors with a connectivity adapter. When put in landscape mode, it fills up 16:9 space and is okay for watching videos or pic slideshows, and tolerable for a short typing session. The nags are that there is just one output resolution and that the keyboard at that time must use bluetooth. If Librem can output more resolutions and connect with all kinds of keyboards, it might be worth buying.

Samsung also has something called DeX these days, which sounds interesting. I don't buy Samsung anymore since pretty much anything Samsung I ever owned died prematurely in my eyes. (A TV, two monitors, several DVD player/writers...) My current Dell monitor is about to surpass the longevity of most previous monitors I've owned, fingers crossed.

https://en.wikipedia.org/wiki/Samsung_DeX

Samsung also has something called DeX these days, which sounds interesting.

As much as I have looked into it, it is not interesting enough, because it does not properly resize all apps. Moreover, for some dumb reason dual-screen (a.k.a. split windows, a very well implemented feature already in Galaxy Note 4) view is not available (but manual resizing with mouse is). So it is not a solid window manager. As a result, there are only mixed benefits to it compared to simply landscaping the Android. 

I don't buy Samsung anymore since pretty much anything Samsung I ever owned died prematurely in my eyes. (A TV, two monitors, several DVD player/writers...)

I cannot quite corroborate that, but looks like you have bought more Samsung stuff altogether, so you know better.

It's also outdated though, perhaps they've improved.