It was a bit unremittingly grim...
Yes, but they were mostly stand-alone episodes with very little plot or character development (not by accident - the networks wanted to be able to show them in any order, padded out by reruns). By comparison, a modern streaming series like - say - just taking the Borg storyline out of Star Trek TNG. IMHO Deep Space 9 could have done with that treatment - it did introduce a long-form plot arc (maybe inspired by some other contemporary SF show...?) but there were a lot of interchangeable "adventure of the week" episodes which I though made it feel very padded. Similar for the 2000s Battlestar Galactica - most of the plot happened in the first 3-4 and last 3-4 episodes of a 20 episode season (and then it turned out that they didn't have a plan after all...) - so I think shorter seasons (often with 50-60 minute episodes c.f. 40 minutes + commercials) works better for long-form storytelling.
Unfortunately, Hollywood has no middle gear so everything has to be long-form and we can't have a few adventure-of-the-week procedurals.
The long wait between "seasons" is awful, though and I suspect it often contributes to cancellations. So, when Severance returns, you're gonna need to re-watch S1&2 to remember what the (twisted) plot was, so only the superfans will bother.
Full marks for "doing it right" to Slow Horses - short seasons, each one a complete story with just enough loose ends anc character development, and the next season is usually along in a year or less (it looks like they shoot them almost back-to-back). OK, it's not a massive special effects-fest - but all of those location shots, car crashes and explosions aren't trivial... Probably the best thing on Apple TV.