Yeah, that makes sense. Obviously there is some investment in setting that up. Seems the first step would be a survey. Probably no quicker way to start an insurrection though. 
Well, one of the nice features is no one gets screwed.
If DCS were to implement this tomorrow, Iron would simply be listed as an owner of all his current modules just like he is now. As new stuff comes out, he can go rental to access the new stuff and he still owns his purchased modules. Or he can ignore subscription mode and just purchase the new content the way he always has and prefers.
I'm not recommending this for AH necessarily, but if a company like AH were to implement this, no one is forced to go out and buy anything to keep playing. They simply start out as subscribers as they are already and can stay that way if that's how they choose. Someone not really sold they want to hook into a sub on this old a game can simply buy the PTO, ETO, or East Front expansion pack for a fixed cost.
But no one is forced to do it either way is the key point.