Most sci-fi shows don’t make it past the 4 season today and most only have like 10 episodes or so per season compared to the 25 or 20 episode before per season.
I think the watershed moment for the short season and long-form (vs. episodic) storytelling was
Game of Thrones - which AFAIK started on premium cable a few years before streaming really went big. Similarly for
The Expanse (which I think was partly motivated by GoT). Both of those shows
really upped the ante for TV SciFi production values. Possibly, sales of DVD/BR "box sets" helped encourage the use of more complex plots that rewarded a re-watch. That's also encouraged a lot more books to be adapted into series.
...and the move towards serial rather than episodic shows probably started back with
Babylon 5 - especially with the 4th season where they expected to be cancelled and condensed the planned 4th and 5th seasons into one
very serialised season (which really worked well). I think that demonstrated that long-form story arcs work best without all those self-contained story-of-the-week filler episodes.
So maybe we just had a brief golden age
just as streaming was starting to appear. I'd rate
The Expanse and
Black Mirror (which were dropped by broadcast/cable and "saved" by streaming) as outstanding shows, so we might expect a bit of "reversion to the mean" here. Then there's things like
Severance and
Pluribus which are so love/hate that I wonder if they'd ever have been made without Apple being prepared to make "art house" sci-fi shows for streaming.
As for only lasting 3-4 seasons, beware "nostalgia isn't what it used to be" and let us not forget... well, I'll let Peter say it:
Not forgetting:
Space - Above and Beyond
Dark Skies
Dark Matter (The Firefly-esque space opera, not the AppleTV one)
...and, of course, the original Star Trek!
Meanwhile, we'll never know what fantastic shows like
GoT and
Stranger Things would have been like if they'd lasted more than 3-4 seasons - perhaps it was better to finish on a high and leave us wanting more? ;-) (...and, seriously, I think it would be a huge mistake not to conclude
Severance with S3).
However, I do think one owned-by-streaming problem is the 2-3 year delay between seasons. I can see how that happens, when you have movie production values you're gonne get movie timescales - but movies are usually self-contained (and movies with ongoing plots - like LoTR, Matrix 2/3, the last few Harry Potters - are often made back-to-back), but it really throws away momentum and makes viewers forget the plot. By the time season 2 of
Pluribus drops I'll have forgotten half of it and will need to re-watch S1 - which people are
not going to do if they were less than totally enthralled by it first time round. Plus, by then, everybody will be raving about
Neuromancer or something else, actors and writers will have gotten gainful employment elsewhere etc. etc.
