Maybe separate cards was the wrong word. (Early 3d cards sucked for 2d.) I guess I meant whether a less complicated hybrid path would have been possible back then.
Issue wasn't so much the cards, but the reason 3D consoles didn't do too well for 2D in improvement was that 3D gaming didn't need as much ram for early polygonal (console) graphics and baked effects. Also no sprite hardware, which only the Saturn and Jaguar had (and CD32 if you consider that major)
As for Sega, the thing is they really were not expecting 3D to catch up that fast or PC's going down. They had most of their 3D investment in the arcades, and the Saturn was basically going to be able to handle what the Model 1 could do which they believed would be a feat unmatched so them having a console that could have those graphics (minus the poly count/size) while they had the model 2 ready would put them in a great position at home.
Then the Jaguar came out creating the first problem. The announcement and the screens coming out and demos along with the Saturn not being ready (outside Japan) had Sega push for the 32X.
Then the PlayStation and 3DO were on the scene in Japan with demo booths, with Sony being the company media was focused on because it was Sony in the 90s, and they had a 3D console with baked effects, and texturing, and less simplicity, and was already marketing hype before launch. Which forced Sega to adapt, creating a hard to develop for mess that would end up costing them money when sales were slow, that couldn't quite reach where they needed to me.
I think Sega's biggest mistake here was at the start of this chain of events. They reacted to the jaguar with the 32X to have something to hold off, but the 32X was weaker than the Jaguar. But Sega was not messing with the Saturns hardware in reaction to the Jaguar, despite it being clear they were not expecting another console to have the capabilities Atari showed (while covering up they were on the verge of bankruptcy and the soon to be realized hardware design issues Atari itself had).
This leads me to believe they though the Saturn they had would match the Jaguar or be a bit stronger than what the demos had them believe, but not to improve the hardware.
Clearly, I believe their biggest mistake, was Sega not improving the hardware after seeing the Jaguar. They could have started to work on that, and wouldn't have to worry about dev issues or additional delays, or needing to suddenly react to the PS1. No 32X would have been needed, although that still may have happened because Sega did not know Atari's situation in the background. But at least the Saturn would have been different in a good way then how it ended up.
Instead they waited, and then when they saw console even better than the Jaguar panicked and made some adjustments that weren't well implemented which caused problems.
Secondly, the model 3 which they made the same exact mistake with, thinking that that home hardware would not catch up on the console end, or the PC prices would lower enough with the right specs on the PC end, when already in 1996 PC was accelerating past consoles already without needing the most expensive rig, in 1997 MDK came out as a big graphical showcase, for SOFTWARE rendering with no accelerator card whatsoever. By 1998 PC was was catching up with model 3 the same year as Sega kneecapping themselves with the Dreamcast which was console that also caught up with hte model 3.
It seems Sega's hubris was the main issue here.
They should have improved the hardware after reacting to the jaguar instead of waiting thinking they were safe, even if they didn't know Atari's situation in the background, they had to have known that they were not as big as they were and they were at that time, still splitting resources across a handheld, a then upcoming console, and a home computer. Any company with more resources would have been able to make a stronger console than them, and they should have figured that out. They were asleep at the wheel at SOJ.
Sega could have easily had a better Saturn without the several issues that plagued it. They could have improved the 2D as well, though that wasn't AS necessary to do.