"Simcade" is the sort of term crafted by the folks that write 4000-word blog posts about how the tire model of [insert game they don't get financial compensation from] is crap. It's condescending and back-handed; it implies the game is somehow like LA Rush or something because it doesn't simulate as much as [insert other game]. It's a flawed comparison, since the only yardstick should be reality, not another game, and the genre evolves all the time.
GT1 was a sim when it released, but it feels primitive now. That doesn't mean it loses the sim status. If the goal is to simulate real life, and it does that, then the title is a sim. GT Sport certainly isn't perfect in the physics department, but nothing is.