If you listen in the near field at low to moderate volume and your loudspeakers don't produce deep bass, then you don't really need room acoustic treatments. Otherwise you probably would benefit from some form of acoustic treatment. However, there is an alternative path where you get loudspeakers that are designed to interact minimally with a room. The Swedish manufacturer Gradient did much work along these lines, but there are others.
If you have a nice system why do you really need room treatments?
Yeah you may need an absorption panel if your room is completely open, ie. No rug or furniture, ie just lonely single chair. But if your system can't cut it in any room then it's a system problem and you should be able to discern a good system regardless of the room. Unless you put it on the roof of your apartment building but the Beatles seemed to have survived that effort
I think people go nuts with all this absorption acoustical room treatment stuff and it looks kind of awful. Once in a while you see a really cool looking diffuser panel and I would definitely want one. But to have a system that works really well without any of the acoustical panel distractions is a wonderful thing.