I think the reality is much simplier. SEGA America and SEGA Europe are very passionate and care deeply about bringing back the classic Sonic feeling and SEGA Japan for whatever reason aren't so much.
They either are too proud to listen or simply lack the deep meaningful and compassionate understanding of just how precise they need to be to actually appeal to diehard classic fans. Or in the worst scenario aren't that bothered. Or don't have the coders with the skill required. There are many possible reasons. But I doubt they are anything sinister.
In fairness I can understand why Sonic Team might not be interested. They are not the same team as back then and they seem to be on the right track to absolutely revolutionising modern 3D Sonic gameplay which has been consistantly good and increasingly better for 3 games now.