So I just realised something potentially terrible for Rosalina mains.
The Regular Tourneys in Tourney mode are pretty infamous already for how they are 3 minutes, 2 stock matches. It's terrible and encourages a campy playstyle, especially since when a match times out and both players have the same amount of stock, whoever DEALS the most damage over the ENTIRE match wins, NOT whoever has the LEAST damage on the current stock.
Since the game literally phrases it as "whoever deals the most damage" - wouldn't that count Luma? This basically makes Rosalina bottom tier in regular tourneys, as she can just be camped out and, even if just Luma is taking hits, she will lose in the event of a time out, even if she herself didn't take damage.