macOS still loses to Windows because of Paint

Who "needs" to paint? Might as well ask for a 3D modeller.

For basic image editing people do need from time to time (cropping, convert format, resize, color changes, annotation) Preview will do.

Is having an image editor built-in to the OS still a necessity? If I did have a need for it, I'd use GIMP, and if I didn't need it, it's just cruft.

I have been both Paintbrush and Gimp installed. Paintbrush usually suffices for quick edits.

Acorn is a pretty good Paint substitute, although it isn't free.