The episodes of "cohabitation" showed that Parliament had more power than generally thought (and that who won the parliamentary elections actually got to govern, even if the President still had a say on some things like foreign policy, military action or nominations of top level fonctionnaires.

With different timetables for presidential and parliamentary elections, you had the opportunity for votes that actually changed who was running the ocuntry.

The change of the presidential mandate form 7 to 5 years (by a referendum in which I voted "non", along with a small minority) has completely eliminated that dynamic, by handing over a compliant parliament to the president as elections for MPs come right after that for president and, so far, have always yielded a majority for the just-elected president.

In the long run, we're all dead. John Maynard Keynes