i don't see why you have to limit yourself to a sprite? using a sprite might make thinsg easier in some case (animations, editable bounding box, solid collision) but using a tiled background is pretty valid if you have the right use case for it. i mean it's just a tileable sprite without some of the functionality ? just cause it has background in the name does not mean it has to be exclusively in the background? you can use it health bars and a ton of other stuff (non background) ?
Again I'm not talking about UI, I'm referring to its use as an enemy. Hes using a tiled background as an enemy and someone suggested to use the tilemap object as an enemy, I don't think that's great but that's my opinion.