2scents, very often the Gemara does bring a Raya from practicalities.
I think you misunderstood our point of the fact that it is being done anyhow. It’s not like I’m planting since it will be planted anyhow. I’m not doing k’siva at all. The camera is marking down the value, or a function of values, for every pixel.
The pixel being red or blue does ot affect the question of whether or not it is writing. It is all the same K’siva, regardless of what’s there. A person is not anymore of a valid mark than a wall.