clone: make an identical copy of.
Actually, the term “Doom clone” was created to describe carbon copies of Doom during the 90’s intended to piggyback on it’s success. But whatever we are splitting hairs.
Unity since version 5 and UE4 could do the same and far more since their inception, so i don’t really get your point.
Also those being better is your opinion, i mean if you are going to improve the visuals you might as well go all in. Again possible with both UE4 and Unity.
Yea, but the downside though is that using Unity/Unreal also means losing all support for pre-existing mods and maps of which there are literally thousands.