Without Dreamcast, who knows what MMORPGs would look like.
But if Sega were to make a new console, it would probably match up with 360, PS3 and Wii. Then BAM. Before you know it, PS4, XBox X and Nintendo X will be released and they'll be screwed once again. They can't win. The only chance they'd have is if they started on a system to match of with PS4, XBox X and Nintendo X right now. Then they'd probably have the best one. But I high doubt they would do that.
But if Sega were to make a new console, it would probably match up with 360, PS3 and Wii. Then BAM. Before you know it, PS4, XBox X and Nintendo X will be released and they'll be screwed once again. They can't win. The only chance they'd have is if they started on a system to match of with PS4, XBox X and Nintendo X right now. Then they'd probably have the best one. But I high doubt they would do that.