You can make the mouse pointer red or solid black in Windows 11/10. Change Mouse Pointer & Cursor size, thickness & the Pointer & Cursor colors.

Byword offers two simple themes. Within its no-frills window, Byword offers only two themes: a light one (black on a light-gray background) and a dark one (light gray on a black background). You ...

The TL;DR is that high contrast between background and text colors is important, and that for many users, black text on a white background is a) most legible and b) most professional-appearing.