I think Ninja Spirit and Splatterhouse were two early arcade conversions that made Genesis fans jealous.
Seeing as the Genesis had two exclusive Splatterhouse sequels and countless SEGA arcade ports (not to mention all the Shinobi games), Genesis fans probably weren't losing too much sleep over the lack of those two games...but they should have!
By the time Splatterhouse 2 came out, no one was thinking about the TG-16 except Turbo fans. But Genesis fans to this day often express a preference for the original.
Neither were common arcade games in North America, so I don't think many console players looked at them as conversions.
During the early days of the Genesis, I thought that it had unique color restrictions like the NES, and that it couldn't do the kind of RGB color and shading that we saw in later games. The first time I played Ninja Spirit, it reminded me of that early Genesis feeling. It's more sort of monochromatic and the selective concentrations of shading reminded me of some of my favorite early Genesis visuals.