Rafa

Same family as the poncho argument: stop trying to seal yourself in, start managing airflow.

Once you accept the above, the goal changes from staying dry to staying warm and controlling how wet, and everything gets easier.

What actually works, in order of how much difference it made for me:

Ventilate aggressively. Pit zips fully open, front unzipped to the sternum, cuffs loose, hood back when you can. Most people wear a jacket sealed up and then blame the membrane. Moving air removes more moisture than any fabric technology.

Wear less under it. Being slightly cool at the start of a climb is correct. If you are comfortable at the bottom you will be soaked at the top.

Consider a poncho or a very loose shell for warm rain. Enormous ventilation, covers the pack, and the airflow does what a membrane cannot. Poor in wind, which is its real limit.

Give up on being dry from the waist down. Rain trousers in sustained rain are the same problem worse. Many people walk in shorts and accept wet legs, because legs generate heat and dry fast.

Keep a windproof layer for stops, since the moment you stop moving is when wet becomes dangerous rather than annoying.

The mental shift is the main thing. Wet while moving is fine. Wet while stopped is the problem, and that is what you plan against.