You also need to consider parents buying presents for kids. "I want the new XBox." There's a lot of parents that aren't going to know or care what the difference is as long as their kid gets their Xbox.
Took me long enough just to figure out (and remember) the main difference between the S and X versions. Then you add in disc and discless versions and it feels like you need a flow chart to decide which system you want unless you're familiar with all the differences. There's no reason for Xbox console names to be so confusing.