MMO on a console is possible, there's no denying that.
FFXI seems to have been the only experiment. Was it that successful? It did quite alright to be honest but think about something...
The MMO market is still a PC niche, just like the RTS. As far as I know, the market barely touches the consoles, so Bioware is putting its efforts into the PC. After all, if WoW can achieve its numbers without touching consoles, why can't TOR?