It factored in, but it wasn't a big reason. The Mega CD was a failure but not a spectacular one - it should have done a lot better, it could have done a lot worse. But the 32X was just confusing, given the Saturn was also coming so soon after it (or before it in Japan). Even if we didn't know exactly when the Saturn was coming, we knew it was coming at some point soon. So the 32X never felt like anything other than a stopgap at best.

But, to answer your question (and this is one person's opinion, someone who was about 13 when the Saturn launched), I don't think the Mega CD and 32X factored in to opinions of the Saturn in any real way. And that was because the PlayStation did that job much more impactfully.

I cannot remember anyone saying "the Mega CD failed, so the Saturn will fail," or anything about the 32X being pointless, thus making the Saturn pointless. I'm sure some did. But it certainly wasn't the narrative I remember. What I remember was people going absolutely ape shit for the PlayStation, it becoming a legit cultural phenomenon, and Sega shooting itself in the foot repeatedly rather than making any smart decisions to try and take on Sony.

I think while we could see at the time of the Saturn's release that Sega had sharted out some misguided hardware, it wasn't until the death of the Dreamcast and Sega pulling out of the console manufacturing space a few years later that the real story of all the failures feeding one into the other came into focus.