How successful are the state-of-the-art (2023) email filters really?
Some references claim that spam detection may reach high accuracy in test settings, but I've thought that email filtering should essentially be as large problem as filtering a whole language. Because one cannot guarantee anything about strings in emails. There will simply be too many possible combinations of strings.
Spam filters might work, but I doubt they can ever reach 100% accurate labeling. And if they don't, they cannot useful, because even losing few important message can be intolerable.