Well Puegeots are Weird
Just kidding I had a 206 when I lived in Malta. Was a cool little car.
From Wikipedia: Hydraulic fluids can contain a wide range of chemical compounds, including: oils, butanol, esters (e.g. phthalates, like DEHP, and adipates, like bis(2-ethylhexyl) adipate), polyalkylene glycols (PAG), phosphate esters (e.g. tributylphosphate), silicones, alkylated aromatic hydrocarbons, polyalphaolefins (PAO) (e.g. polyisobutenes), corrosion inhibitors, etc.
Many hydraulic fluids are corrosive and eat plastic, paint, rubber etc.
Oil is a bit less caustic.
The stator windings seem to survive just fine. Mine are 36+ years old and keep right on working.
On the 350/400 series theres no oil in the stator cover. I looked at the 550 engine I have and its oil tight as well