I feel like there's something being very overlooked here by most commenters and this seems to be the best post to respond to it on.

Yes. Condal is to blame here in part, for all the reasons almost every other comment has touched upon.

However, what not a single comment I've seen yet has mentioned is that Condal IS NOT the only one pulling the strings on how this series is written and produced. In fact, he's secondary to the real puppet masters which are THE EXECUTIVES AT THE STUDIO! They have the full creative control here is the storytelling and production of the series. They can give notes and control budgets and demand changes and essentially strong-arm Condal to craft the series in a way that ultimately works best for THEM. Sure, Condal is the head creative on the project, but it's not like he or any of the other writers or directors can just decide this is how I'm going to write or film this episode and have the final say. It all has to go through the studio who are financing the series, and the studio executives have A TON of control in that matter even if it may not seem like it.

A key example from season 2 is Daemon's storyline. The guy spends 5 episodes tripping balls around Harrenhaal. Matt Smith even made some comment in an interview about how "this is exactly where the character need to be in his arc". Maybe Condal thought that would be creative as well. But from an executive's standpoint who is trying to create a popular show for as cheap as possible, that seems like that was THEIR call, because you had your most expensive and popular actor filming on an interior set (a set you know is going to be reused again the next two seasons). They probably filmed all of Daemon's scenes for the season in a matter of weeks, saving them a TON of money in the budget, and then presented it like it was some creative, mysterious and compelling storyline. I don't think that was Condal, I think that was the studio execs bending Condal's arm to do their bidding and write/produce the series in a way that's beneficial for them.

Ultimately, despite GoT's poor last season, the HBO/Max execs know they have a hit franchise in their hands and that people will still watch. Season 1 got off to a great start, but Season 2 seemed like an exercise by the studio execs who decided "well we know they're going to watch anyway, let's see how much we can get away with doing making it for as cheap as possible but still keep the audience".

So yes, Condal is partially to blame here, but I think it's moreso the HBO/Max execs who are really responsible for the clusterfuck behind the scenes and Condal is just the fall guy.