On a literal level this is correct. Dreamcast hardware was used in Arcade machines as the Naomi board. Xbox used PC parts and the controller ports were USB 1.0 just with different connectors. You could splice USB cables with Xbox controllers to work on PC and many did. You have to understand tho. SEGA fans were homeless. MS had connections with SEGA from DC and had a lot of ties. It was the perfect place for SEGA fans to go to. Sony and Nintendo were seen as rivals/enemies for years.
I was more referring to just the general vibe. Arcade ports were a big part of Dreamcast while Xbox was characterized by PC ports like Doom 3 and Morrowind. There's a big difference in feeling between PC and arcade gaming.
Bet with Liquidlaser: I say PS5 and Xbox Series will sell more than 56 million combined by the end of 2023.