They should have moved the characters on, and explored a more serious avenue for them.

They literally did. That was the crux of the 9th season. It flopped and the series was cancelled.

They could have built a medical dramady around these characters, but they took the “safe” route, and now they’ll be gone in a season or two.

That’s always been the formula for these revivals. They spend half the budget on promotion, churn out 8-12 episodes, and then throw the concept back into the garbage bin.

I’m amazed they haven’t tried to revive Friends yet, using this model.