Do the people really need the king to be anything apart from not destructive? The Hand is inevitably the one who makes changes, and since it's Tyrion doing that he's not likely going to curtail the rights of the small folk more.
Well, Robert wasn't actively malicious, and it could even be argued he wanted to be a good king. He just didn't want to rule, which is a problem in a monarchy; apart from their governmental role, the monarch is a psychological focusing point for the people. They're a way to put a human face on the country, and even when the monarch is entirely relictual there's still value to that. When the king stops seeming human or saying anything or being visibly the king, that's how you get people stepping into speak for him and interpret things, which is a short hop to, well, the Sparrows.
All the bullshit with tournaments and ermine capes and pageantry is mostly there to make the king look good, yes, but making the king look good helps keep people from trying to usurp power when no one's looking. Holding court and throwing festivals, on the other hand, are to make the king look human, which helps keep people trying to bring their problems to the attention of the monarchy and/or griping about the king instead of revolting. People can be foolish in ways that encourage the populace to whine and power through it in ways countries can't.
With Bran, sure he's not malicious or destructive, but he's also not human. Who knows if his decrees are for the good of the realm as it is or for some greater good that only he can (fore)see? What else is there to do with that uncertainty but to worship him and hope his grand plan includes your happiness? Even if he's personally committed to being a good king, the image he presents -- and that will be all 99% of Westeros ever sees -- encourages theocracy. We've seen how that goes.