Talk about killing your buzz and get forgotten.
To just throw out a single 60 min episode and call that your 50th Anniversary is a slap in the face and showing no respect to this show.
I agree with this. Though, I want to add that I don't think there are any "bad guys" in this story. I think the BBC cares and Moffat definitely cares.
It appears to be a combination of budgetary problems and mismanagement. They can at least fix the mismanagement and get a regular production going at whatever rate they can afford. Whether the BBC has the leadership to actually do this, I don't know!