Thinking logically, without anything to clean the valves on a DI engine, I want something to help reduce the amount of oil bathing the back of my valves.
My last EB f150 had one too, cuz DI turbo life! My non DI engines I don’t worry about the can because the injectors do most of the work of keeping the valves clean.
Having said that, I can still see the value in them even on non DI vehicles. Even if I couldn’t, I wouldn’t spend much time arguing with the supporters of them because it’s their ride. Who am I to question how they spend their time and money for their vehicles?