Testimony from the field.......
Having recently taken over some of the cooking from my debilitated wife, I can testify to the contrary.
She has two second generation, well seasoned cast iron skillets that produce sticking.
She has new and rather expensive lined cook ware by two different manufacturers that allows no sticking, even with little or no oil.
The new stuff is in fact non stick and is far superior to the old two generations old and totally seasoned cast iron
What are you, washing her cast iron in the dishwasher?
If the cast iron is washed with soap, it removes the seasoning of the polymerized cooking oils.
Just let the pans cool then wipe surfaces some with salt.
I made a mistake as a teenager working in a restaurant by ‘cleaning’ the head cook’s egg frying pan with soap and water. I thought he was gonna kill me! ......................
How often does the cast iron pan get washed with soap and water ?