was John’s main concern appearing as a good husband in the yellow wallpaper ?

It could be argued that John's concern was appearing to be a good husband, but if so, the irony is that his actions show a serious disregard for his wife's well-being. He does seem to show concern over her "hysteria," so much so that he removes them to the country. However, the symptoms suggest a deeper problem that illustrates how patronizing he is, but he is blind to all of this. So by attempting to be a good husband, he continues to act as an oblivious and distant one.