The term "most irremedial" implies a state of being so hopeless that it appears impossible to fix or resolve. The antonyms for this word include "fixable," "solvable," and "resolvable," all of which refer to more positive situations where a problem can be addressed and overcome. Additionally, "manageable," "treatable," and "healable" suggest that while the issue may be challenging, it is not insurmountable. Other antonyms for "most irremedial" may include terms such as "reversible," "improvable," or "correctable," all of which describe situations where there is room for improvement and positive change.