I don't feel Carol was written off for decades; but he had a chance to rewrite or refocus her.

I thought it was essential that her Rogue experience wiped away her memories and the emotional connections. Though her memories returned, it did take a long time for the emotional connection as I recall. Then she was experimented on by the Brood, became Binary, joined the Star Jammers so not a total neglect but sorta put in a specific area, for the not so widespread Marvel industry.