Frankly, it's very rare that a big TV show doesn't drop in quality in its later stages - particularly in the US, where the massive riches on offer incentivize everyone to flog every horse way longer than it should be (it's ironic that GoT is the one show that's gone the other way - rushing to the end instead, because of the massive riches on offer from Disney) and the actors get a little staid and tend to mail it in.
I'd argue that even the likes of The Wire and Breaking Bad dipped in their final seasons (they were still very good - but not as good as either show at their peak)…….
So obviously the petition is a ridiculous expression of butthurt fantasists...….
…...although at the same time, although it would never happen, it would be fascinating as a practical study to see what another group of writers would do with the same cast and material!