When you can see the fix but can't make the whole org move

I laid out the better approach in the meeting and heads nodded, and then everyone went back to their own teams and nothing changed. I don't manage any of these people, so all I have is a good argument and my reputation. On my own team I can steer things, but the moment it crosses into someone else's world, my pull just runs out. I can see the fix for the whole org and I can't get it to actually happen.