Official 
post (which disavows Roger Craig Smith)
Seriously why. Sonic and the Black Knight was the last one and it was also the last time you could beat the final boss to a kickaas buttrock theme song. Why don't we have this anymore?
Because Sonic's main cultural impact is inflation furry porn now instead of creating 3 halfway okay platformers 40 years ago.
They can hardly afford enough money to run the air pump going straight into knuckles balloon knot nowadays.