This is potentially a clever way of getting round the fact that his speaking time is counted as part of his party's campaign for the legislative elections*.
The French media must maintain a semblance of pluralism of opinion and each candidate's speaking time is counted. The speaking time of the President when he is not speaking directly to the French people as part of his duties is counted as that of his party.
Podcasts are not subject to this regulation and ARCOM does not measure the audience for podcasts.