That was really boneheaded on Sega's part. They introduced the DC in Japan first, killing the Saturn which was quite successful there.
Had they waited, or at least launched in NA/EU in 1998, they could have kept money coming in from Saturn in JP while getting back into the market elsewhere.
In my teens, my older brother worked at a computer shop and back then was a hardware geek, and a Matrox M3D, and frankly compared to something like a Rush or Riva 128 the M3D was pretty good outside of some blending moire. That I'm talking about visual vs perf says something... and Dreamcast got the version AFTER that...
The biggest thing was their Tile based deferred rendering, which made it easy to create an efficient GPU with a relatively low transistor count.
Also, 3dfx pattern of 'chip per function', aside from it's future scaling issues, would have been a higher BOM.
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All of that said, ever wonder what the video game scene, or NVidia would be like today, if the latter didn't derp out on their shot at the Dreamcast in an SEC filing, which caused them to be relegated to the video chip for the Pico?
It was efficient but the performance was definitely the lowest of all consoles that generation.
Oh yes that I definitely knew about, the rushed Saturn launch out of nowhere, as well as its early retirement to make room for the Dreamcast, soured a lot of people.
A shame too, the Dreamcast deserved so much better. It was a great system, and pretty prescient too, at least on the GPU side: Sega America wanted to go with 3dfx, Sega Japan ultimately went with PowerVR, 3dfx turned out to be a dead end, while PowerVR endured until fairly recently (if mostly in the mobile / embedded / power efficient space).