Depends how you define carnivorism
If carnivores are animals that eat meat in nature, then cats are carnivores
If carnivores are animals that absolutely require meat to survive, then cats stopped being carnivores a little while ago.
Cats, even domesticated species, are still obligate carnivores, as in they will die of malnutrition eventually if they are put on a non-meat diet.
They 100% need to eat meat to survive. Vegan cat food will kill them slowly as they can’t properly process the proteins in plants.
Outdated information. We recently invented synthetic taurine and solved that problem.