Fired after 30+ years of employment without any write-ups, suspect retaliation [California]

Hi, r/legaladvice. This is actually for my aunt. She was just fired today from her job as an editor of the local newspaper. A few days ago she was in a work meeting and her supervisor asked her if a project she was working on was sustainable. She asked him what he meant - cost-wise or labor-wise? He responded, "Well, do I have to explain it to you?" The next day, he called her into his office and yelled at her, questioning her ability to lead. Today, she was fired and the reason given was that her supervisor lost confidence in her. She has never been reprimanded or warned about her job performance. This supervisor just came on in March of this year. We suspect that he was hired to eliminate some of the newspaper's higher earners to cut costs. I know about the whole thing with being an at-will employee, but we were wondering if she could do anything legally. She noted that there were other women in the workplace who have been targeted for possible termination and it has become a hostile work environment since this guy was hired. More information can be provided if needed. Thank you!