why cant we just have a unit list and exclude units as we want when hosting a game like in TA, so we could exclude "broken" units as we like
Because the game isn't finished. Uber has said they're likely going to do this eventually. In the meantime, stuff like this could very easily be modded. And because of how server mods are, you can make this so everyone in your lobby is on the same mod. So if you want to play a multiplayer match that doesn't have the Dox? You can do that. Just gotta make the mod.
its obvious that you could do this with mods, but with a list there would be no need for this... just a list and everybody is happy even with vanilla