I think the classic readers/tarot/mediums are 99% pure bollocks- I would guess 50% know they are charlatans, and the rest fancy themselves as skilled and reason everything to confirm that bias (like 'I'm an empathy' stuff.)
However, I do believe we aren't even close to working out how the 'spirit'/ essence/ soul/ will/character/presence/ unspoken communication' stuff works. And I think in the classic 'Western' world we are closed down to all of it, with a heavy bias towards western forms of rationalisation, allowing us just the one form of magical thinking in organized religion around one God.
Personally, I don't think there is anything more irrational about believing eg that spirits can leave bodies, pass through others as host, or that we can sense or channel things with loved ones (eg a twin) from a distance, than that one God created us, there was a miracle birth, resurrection etc.... or for that matter big bang theory.
There are countless mind-blowing mysteries, which we haven't even begun to solve about how beings work. I think I would be pretty arrogant to conclude I knew what had no basis, and what did.