It depends on how the supposed feature is implemented. If it's the SimCity variety of always-online (running everything important client-side but requiring a response from the server every 5 minutes or it kicks the player out of the game) then that could easily be removed in the months before the console's release. They could still maintain their online strategy, just make it so that singleplayer games can work offline. If it's something more integrated then MS would probably be stuck with it, and they have to hope that they're able to sell its value to consumers.
Like it or not, the rumours are there, they've come from multiple sources (including a usually reliable MS blogger) and have been tacitly supported by the statements of a Microsoft employee. Now, I'm still holding out hope that MS aren't this stupid. But in case they're not, is it not better to send a clear signal to them now not to pursue this strategy? If we wait and they genuinely are planning this, the reaction may come too late. It's the precautionary principle.