If the Brim Object Gap (Prusa, Orca, Bambu Studio and Creality Print) is set to Zero then the brim and the model are effectively one and the brim has to be cut off. If the gap is set to 0.2 then there is a small visible gap and the brim generally peels off. So if there is a gap is the brim actually doing anything to hold the print down on the bed or is the print free to lift off of the bed???.
I use a 0.15 gap and your thought is correct. But it works. The magic of 3D printing sprinkles the wanted fairy dust onto the object to hold it in place.
I use a 0.1 gap myself it works there is enough squish it touches but I usually stays on the bed.
See I didn’t know that. Magic. And here I thought it was science. Who knew!