Truth is, we all know what the problem is and we all know how to fix it. So does Sonic Team.
They don't care.
Almost all Sonic games, even the shockingly bad ones (you know which), have churned out huge profit. They're not fixing what isn't broken from the marketing department's point of view.
They probably see it as fair in the end, as Sega have had a string of critically acclaimed but poor selling franchises (Panzer Dragoon anyone?), and I guess they were sick of eating poorhouse soup.
Granted, I think it was more of a publicity problem, than an audience problem, but still...