If you watch or can watch HD as a minimum and some 4K then the Samsung wins. If not, then go for the Sony.
Poor quality sources don't look good upscaled on UHD models so you should go for the FHD one if you have no plans on 4k sources.
I'd be concerned on any TV relying on the TV direct for media playback, limited video and sound format support.
Any reason why you only are looking at small screen sizes and also 2017 models instead of 2018 ones? Generally UHD itself is pointless until you go up to larger sizes. If you are using a TV already, you may just be better sticking with what you have.
My question is which TV will produce more quality/real (more details, colors etc.) picture?
Basically the Sony is a better option because you do not have any high quality sources. Less upscaling=better quality picture for poorer sources.
The Samsung will have an edge over the Sony with colour and smart TV though, although the better colour of the Samsung will probably not be noticeable unless you are using a source that has HDR.