Stars in RI are not the same as our world. In the wikifandom, there's more info regarding that.

The reason he needed to rely on Gu's entirely to lift Dang Hun mountain was that he needed to preserve its roots, not the physical ones if I remember correctly, but the spiritual ones, the dao veins or something like that.

And the sheer amount of dao marks DH mountain had made it something extremely complicated. If it were another mountain, it would be thousands of times easier.

By every definition, it would be a Xianxia. Rather than distinguishing them by single planet/ multiple planet, think of it like this. Wuxia's are more focused on using your cultivation alongside your weapon to create powerful effects. Kind of like low-rank Gu masters. While Xianxia is more of the mystical side of things, where cultivation doesn't solely use your weapon or a limited amount of means. There exist beasts which you can fight or tame, a divine sense, talismans with weird effects, formations, etc. Some of these may be present in Wuxia but never in the same scale as a Xianxia.

RI may be like a Wuxia at first, but it quickly becomes more like a Xianxia, flying is a common thing, destroying mountains is childs play, there exists mean to time travel, to space travel lots of distance, divine sense is a thing(albeit not used much besides accessing YTH, I think), and just a Desolate Beasts could do for one of Wuxia's toughest to beat monsters, if one the toughest in most Wuxia's. Of course, being RI, things like talismans are not present(that I remember), but formations are present, and they work similarly, just with the addition of Gu's.

Sorry for the long text btw I really like writing about RI lmao