If you're out of the loop with French politics, the wiki entry for Bayrou is worth a glance:

73 years young...

On 21 June 2017, he resigned from the government amid an investigation into the MoDem's allegedly fraudulent employment of parliamentary assistants, initiated earlier that month.

Bayrou resigned [as Minister of Justice] several days before the 2017 legislative election, only 35 days after he had taken the post.

Since September 2020, Bayrou has been the haut-commissaire au plan (a high commissioner of planning). In 2024 he has published a single note. It was in January. Nothing since. Nada. Since taking the position, the high commissioner has published a total of 17 notes.

I live in France and thought this guy was retired for some reason.

I know that Macron is trying to square the circle after his little stunt with the elections left and France an ungovernable mess, but naming Bayrou prime-minister sounds more like a move to piss off as many people as possible in the parliament than an attempt to end political instability.