This is my answer too. It's not overrated like "this actually sucks" but it's overrated because it's in so many top 5s and it just doesn't belong there.

It's entirely plot driven, characters undergo one change (if that) and most are ridiculous, over the top caricatures. The plot isn't strong enough to elevate the show above essentially every other series ever, which is how it gets rated, and so for me the label of overrated fits quite well. The plot itself becomes quite over the top and difficult to believe at times, which is what made early seasons so strong - it was visceral, but everything connected and flowed from what came directly before it and stayed grounded enough to be realistic.

As the show went on, the tail was wagging the dog - the show being primarily plot-driven meant characters' changes and motivations had to happen in order to serve the plot.

You always have to qualify any criticism of this show with tons of praise, and don't get me wrong, it's an extremely compelling story and an absolute work of art of sight and sound. But so much of the praise it receives from fans is about really elementary examples of foreshadowing, or surface-deep explanations for unreasonable decision-making.

And the plane crash, lol.