>>58640578Because psychic in gen 1 was a god-type with no real weaknesses (all bug-type moves were weak as fuck, and gen 1 psychic was actually immune to ghost instead of weak to it, not that it really mattered when the only ghost-type attack that didn't do set damage was lick and all the ghosts were part poison-type) and only resisted by itself, so they needed some type to nerf it by acting as a hard counter.
Same why fairies are immune to dragon-type attacks. Before gen 6 dragon attacks were extremely spammable because there was only one type that resisted them, and since dragon-types almost universally have extremely high stats it made spamming choice banded outrage way too powerful.
