3DS should have a great legacy at this point. As others said, it is the handheld that withstood the mobile takeover and still managed to finish with lifetime sales that will likely only be 15m or so below the 80m selling GBA. It also will go down as a total JRPG haven where the genre flourished like it hadn't in years, and a strong software lineup in general.
Wii U should have a similar legacy to GCN. Great software lineup that not nearly enough people bought the system for. But like GCN it won't be an outright failure, just a disappointment.







