I bet there are still people thinking that 20 megapixels (20? 23? 25? the Exmor RS IMX300 in the Xperia X is 25 Mp) are better than 8 megapixels. This is not always true: you may personally check the difference between the best 8 Mp cellphone camera and any old 8 Mp reflex (the latter would always win, even if with a cheap lens). The real "magic" in cameras is basically all about physical characteristics, and no hack can actually outperform physics laws and usual human issues (a blurry photo is mostly an human error, not a camera/lens/sensor limit, while most of the times you'll want to shoot pics in less than ideal conditions).

The "more megapixel" trend in cameras has always been a catch-22 thing. More megapixels meant you could stretch down the image to an apparently better quality, thus every manufacturer didn't care too much about sensor/lens quality as long as it could go on in the megapixel race. A good full-HD image (that is, two puny megapixels) would appear perfect on every cellphone, even the most recent ones sporting uselessly high PPI values (ah, those ridicolous "retina"-like buzzwords for gullible fanbois). And a 4k full-HD image is actually 8Mp. The megapixels race will eventually come to an end, like the sound resolution decades ago - today, most people can't discern 44.1 kHz 16 bit stereo from any higher values (especially if using earpieces).

That is, I would be OK with 8Mp on Xperia+SFOS.

The stock Sony camera app just applies some "magic trick" - aka software library - to do some filtering and noise reduction. Maybe because of patents, that library would only work if fed with some DRM-like key. else it would just resize down to 8Mp, actually castrating the camera. This is why we should talk about that noise reduction and low light thing instead of Le Twenty Mega Pixels meme.

There's yet another reason to be happy SFOS guys wisely chose the Xperia X: it uses a normal USB plug instead of USB-C and a normal analog 3.5mm ear plug. I'm getting sick at upgrading my hardware (or buying new adapters) because of certain fanbois gullibility. We are not anymore in the 1990's, when you paid to double your performances every 18 months. Moore's law just degraded to Murphy's law, and even if you have a very good sight most of the time you'll be checking your phone in a badly lit environment, sending a quick pic that will just get a few pathetic Like's before getting forgotten by anyone, calling someone hoping that the claimed 11% battery left will actually last until the called dude clearly heard the urgent things you had to say.

tl, dr: better specs and features make me happy, but I'm always the last rat to follow the piper.