The phrase "being all for" indicates support, agreement or enthusiasm for a particular idea, action or proposition. Some antonyms for this phrase include "against", "opposed to" and "anti". These words signify an opposition to a particular idea or action and convey a negative sentiment towards it. Other antonyms for "being all for" include "indifferent", "uninterested" and "apathetic". These words imply a lack of interest or concern towards a particular idea or action and suggest disengagement or detachment from it. In contrast to the phrase "being all for", these antonyms undermine the level of commitment and enthusiasm for a particular idea or action.