I love the Dreamcast. Years later, games like Soul Calibur really stand the test of time, both in design and in looks. The gameplay, sound, and visuals are all stunning.
There are many theories of Sega's console demise, from hackers having found a backdoor, to the timing of the PS2's release, to Sega's relationships with developers, etc. It's irrelevant. That was about a decade ago. If Sega were to revitalize their franchises and build new relationships with developers, and maybe pocket a few developers to put some more talent in-house, they could make a run at another console. But that involves a lot of what-ifs and a lot of brilliant moves. It's something I believe Sega is capable of, but either won't do properly or won't even bother at all.