No, it has to do with the fact that ability to acquire fine motor skills vary a great deal between individuals and many students simply cannot learn to write at what educators consider an acceptable level of quality, no matter how many hours you force them to do lines, no matter how many times you tell them they are sloppy, or lazy, or stupid. They simply cannot do it, any more than a one-legged student can do the triple jump. But unfortunately these students and their unique needs are hard to detect and mostly they are just stigmatized as slow or difficult.
I don't know if you understand how harmful and undermining it is to be set up to fail like that. It's cruel. Once upon a time, it might have been worthwhile overall that some students had to suffer that, but it no longer is.
We just do not have the facilities to address the unique needs and very common disabilities of children, we've gutted all of that. If you want to teach cursive, how about we first start supporting students with disabilities. That's something parents SHOULD be upset about. This is just bullshit distraction, because it's designed to be a bullshit distraction.