Can this hell of a mess touch-ups be corrected easly or repaiting whole part is the only way?

Bought a car that I saw had some DIY touchups, after cleaning the car tho it looks way worse then when it was covered in layer of "dust".
I have no idea about bodyworks so need some info, is this easly fixable or its better to paint whole part? Should I just ignore it if it doesnt rust? Most of them except two are not even visible when I stand next to car without my face "glued" to door.
Its on 3 doors 3-8 spots like that per door.