Yep, you only have to look at someone with something like dementia, who was once perfectly lucid, to see that mind and brain are one. Take various psychoactive drugs and one can clearly see that the mind emerges from biochemical processes when we interfere with those processes with those chemicals. No mental gymnastics are necessary, which is necessary when mind and brain are seen as distinct. I think it boils down to people not wanting to die and a separate metaphysical mind permits the comforting possibility of continuity after physical death.