I agree with this completely.The problem lies in the way projects happen at Disney. Tons of ideas are proposed and very very few of them every get selected to move beyond just the proposal stage. Then they get further fleshed out, developed, altered, etc before they get proposed again. Of those that make it this far, even fewer get through to actually getting greenlit. At that point, things really get intense as every aspect is looked at again and really fleshed out. Changes can and do occur right up until opening of an attraction. But being greenlit isn't even a guarantee of something being built. Things can and do change at all stages of the process.
Rumor reporting never states at what point in the process things are, just the proposal itself. So is it just an idea that was proposed, is it a serious proposal, is it being considered to be greenlit, has it been greenlit... we just don't know. So a MASSIVE grain of salt must be taken with every rumor.