Picard isn’t really any darker than what we see in DS9.
The only difference is that characters emotionally react to negative things more. In Bermantrek nobody shows their anguish, they react to it stoically and mutedly, then they cut to a comic scene to raise the mood.
Or comedic as far as TNG was allowed to go; Roddenberry's ideal was that humans would evolve to be like Vulcans over the last 80 years. This is also reflected in DS9 and VOY, and retracted for ENT given the time period in which they were in. Berman had quite the job in trying to keep true to that WHILE providing engaging material. If conflict doesn't come from within the crew then exterior baddies are necessary and unlike TOS nobody wanted bickering, as by season 2 almost everyone hated Pulaski. It's amazing Gene authorized her crotchety side.