Everyone should be clear. Changing resolution in ANY LCD on ANY device, (Phone, Tablet or Laptop), is problematic and likely not what you want. LCDs, (and possibly other tech like plasma), are digital unlike the old analog cathode ray tubes of last century.
The only slight exception to this, is specific integer reductions. For example taking 1920 x 1080 to 960 x 540. And that is only dependent on the LCD monitor supporting such.
Using anything else, (assuming it even works), will lead to fuzzy screens. The amount of fuzziness depends on the graphics card, the LCD and the content to be displayed. So, if you don't see any fuzziness, that does not mean you have a solution. Just means with that specific combination you don't see it.
In the case of desktop LCDs, they kinda have to support odd / non-native resolutions. This is because you need something to actually use the computer, to get to a LCD native resolution. For example, some computers boot to VGA resolutions of 640x480 or 800x600. Neither of which are integer reductions of most higher resolution LCDs. Whence the computer is done booting, the OS takes over and sets the graphic card's output to the LCD's native resolution.
Everyone with vision problems, whether minor or major, (and this includes ME), should set the OS user interface to support their needs. We created a section on the Wiki for thus purpose. It's vague, because it's GUI dependent. Feel free to add details for a specific GUIs.
https://wiki.pine64.org/wiki/Pinebook_Pr...eadability
I'd rather have a high resolution monitor, and make the items in it, (be it text or icons), larger. Than less resolution. This is because letters and icons with more detail, are easier on the eyes, which makes them easier to interpret. Even if you have to make them bigger.