Is it permissible to have a family gathering for a New Year's Eve dinner with the intention of it being a gathering, not a celebration, knowing that the ruling on New Year's Day is that it is an innovation (bid'ah)?

If you believe that celebrating the Gregorian New Year is an innovation (bid'ah), then designating that day for a communal dinner, even with the intention of merely gathering, is considered a celebration that should be avoided. Ibn Taymiyyah stated that what people do on such a day, such as preparing food and lighting fires, are reprehensible acts, and that considering this birthday a feast is part of the religion of Christians and has no basis in Islam. He emphasized that it is not permissible for Muslims to imitate Christians in anything specific to their holidays, whether it be food, clothing, or anything else. Furthermore, it is not permissible to hold feasts or sell items that aid in such celebrations. Rather, their holiday should be like any other day, and Muslims should not distinguish it with any of their rituals.