Troop experience. Is it necessary or not?

Yeah, that's exactly what I'm talking about. Experience is such a strategic element of the game, leading to a completely new and different level. It's a pity that no one understands this. After all, only a select few have tried the game with experience enabled. And they are the strongest players in the world. The rest don't even have a clue what it is, but they still try to argue.