The showrunner recently explained why the current Dexter series feels different from New Blood.

Even though there is a 3.5-year gap between them, Dexter: Resurrection serves as a direct sequel to Dexter: New Blood. The latter was always intended to be a limited series and the definitive ending to Dexter Morgan's story, following Michael C. Hall's request to conclude the character's journey in a single season.
But to the surprise of many fans, Dexter: Resurrection unexpectedly became a reality. The decision was welcomed by viewers, especially after years of criticism directed at the ending of Dexter: New Blood across social media.
While Dexter: New Blood and Dexter: Resurrection are nearly identical from a technical point of view, sharing the same aspect ratio and a very similar title sequence, many viewers out there have noticed that the two series feel very different. This is despite the fact that only 10 weeks separate the events of the two shows. According to showrunner Clyde Phillips, that difference was intentional.
Speaking with Collider, Phillips explained that Dexter: Resurrection was designed in part as a response to fan feedback. After paying close attention to audience reactions to New Blood, the creative team intentionally went back to the storytelling vibe that actually defined the original Dexter series.
Phillips said that New Blood felt too sparse, a result of the super challenging production conditions. Filming took place during Covid across Massachusetts in difficult winter conditions, which made it the most difficult shoot of his career.
Coming out of that experience, he and the team wanted to give audiences what they believed fans were asking for. By paying attention to online discussions and reactions, they came to the conclusion that many viewers missed the pace and energy of the original series. As a result, they decided to bring those familiar elements back in Dexter: Resurrection.
It comes as no surprise that Phillips pays attention to fan feedback. In many interviews over the years, he has repeatedly said that he follows discussions within the fan community and listens to audience reactions. Whether it's Dexter: Original Sin or Dexter: Resurrection, Phillips never actually stopped showing interest in understanding how fans respond to the franchise.
The idea that Dexter: Resurrection is closer to classic Dexter is something that didn't became unoticed by fans in recent months. Despite the new setting and different circumstances surrounding Dexter Morgan, many viewers think that the series captures the spirit of the OG show.
That success has very little to do with.. technical details and much more to do with the writing, especially the way Dexter and the supporting characters are written and portrayed. For many, that return to familiar storytelling is what actually makes Resurrection feel like classic Dexter once again!