This explanation contradicts a halakhic midrash cited in a baraita.

If we maintain that “all mitzvot of a son with regard to his father” refers to those mitzvot that a son is obligated to perform for his father, and the mishna rules that “women are exempt,” are women exempt from these mitzvot? This is contradicted by a baraita: But isn’t it taught in a baraita concerning a verse that addresses the mitzva of honoring one’s father and mother: “Each of you [ish, literally man] shall fear his mother and his father” (Leviticus 19:3). I have derived only that a man is obligated in this mitzva. From where do I derive that a woman is also obligated to honor her parents? The source is from the same verse. When it says: “Each of you shall fear [tira’u] his mother and his father” (Leviticus 19:3), tira’u is a plural verb, indicating that there are two obligated here, son and daughter.

The halakhic midrash cited in the baraita teaches that a daughter is also commanded to fear her mother and father. Consequently, “all mitzvot of a son with regard to his father,” with regard to which the mishna states that women are exempt, cannot be explained as referring to obligations of a son toward his father.