Why, is 1366x768 still the standard for laptops? It really doesn't make much sense, does it?
If 1080P became the default standard for laptops (budget laptops included), then the economies of scale would make the panels for that resolution, nearly just as cheap as current 720P panels, wouldn't they?
So why not change? Entrenched mfg infrastructure? No laptop makers willing to go out on a limb to change the status quo, and put 1080P panels in their budget laptops?
The reason for this is actually quite straightforward and doesn't really have anything to do with cost cutting as such like a lot of people are suggesting.
1366x768 is so common for laptops for the exact same reason that 1080P is common for desktop monitors, they have the same PPI.
When a manufacturer makes an LCD panel, they don't make it in the final size, but instead make a huge panel (
a mother glass) that is then cut into smaller pieces. For desktops, the most popular mainstream size right now is probably something like 21.5" (
#1 best seller on Amazon), this panel has a PPI of 102.5 and thus the mother glass also had a PPI of 102.5. So if you were to cut 15" panels (i.e. laptop size), then you would naturally get panels with a resolution of 1366x768.
This is also the reason for why you almost only see 16x9 monitors these days and very few 16x10 monitors. The shape of the mother glass means that manufacturers can get more panels if the cut them as 16x9 panels.
So long story short, 1080P won't be mainstream on laptops until 1440P becomes mainstream on desktops (again these would have roughly the same PPI at 15" and 21").