Reguarldless of whether or not you like SFC3, Activision's acquisition of the TOS/ TMP license killed SFC. Without the license, an improved version of SFC2, excepting OP, became impossible. The release of SFC3 split the existing community into two factions, SFB and anything-but-SFB. Since SFC was concieved as SFB-on-the-computer, I have little simpathy for the latter faction. I found Activision's heavy-handed control over development and content rather rude.
Although SFC3 attracts people that may not be interested in SFB, SFB is at the heart of the game. Those longing for a more complete version of SFB will not buy another version of SFC until it goes back to the SFB ruleset.
I don't think that the hatemail generated by SFB enthusists harmed SFC3. Buying out the competion and destroying their product line is an unfortunate but common buisness practice. This is the essence of "dog eat dog." Could Activision have believed that their content was so much superior to the origional as to win over Taldren's existing customers? Such arrogance is not unheard of. I doubt they lost money on this venture, but it is possible that Activision had unrealistic expectations from initial sales and connections with other products.
Activision's unusual lawsuit against Viacom and the FTC investigation of Activision reveal a company in trouble. Only the depth of the trouble is in doubt.
The only hope for the future of SFC is that Activision is in big trouble. I think the only reason they published SFC3 is because Taldren could deliver a higher quality product than Activision was capable of at a very modest price. If Activision has to sell off rights and licenses and/or realise that they must develope products to meet every concievable nicht of the ST franchise, then there is hope for SFC. If Taldren can either convince Activision to give them free reign with SFC (scoff, scoff), or Activision sells the necessary rights to a willing publisher, only then will another SFC game be created. Life would come back to SFC.
These are some pretty big "if's," but there seems to be a light at the end of the tunnel. Freight train?