There are a few that come to mind, but nothing I can think of as super recent.
- After Life, Simon Funk: https://sifter.org/~simon/AfterLife/
- Most of Ted Chiang, but particularly Liking What You See: A Documentary: https://webcache.googleusercontent.com/search?q=cache:vSPLnv...
- Also Ted Chiang: The Lifecycle of Software Objects (not really pessimistic or optimistic, just thoughtful)
- Her (Movie), melancholy but ultimately hopeful
- HPMOR (Harry Potter and The Methods of Rationality): http://www.hpmor.com
- True Names, Vernor Vinge: http://www.scotswolf.com/TRUENAMES.pdf
- Permutation City, Greg Egan (accurately predicts AWS 20yrs early along with a host of other super interesting ideas)
- Star Trek TNG is the classic example of optimistic Sci-Fi, but the more recent Enterprise is also good.
- The San Junipero Black Mirror episode
- I wouldn't call The Expanse optimistic, but it's probably the best sci-fi show on today.
---
For some contrarian anti-recommendations which can be just as useful:
- I thought the culture series was bad, in plot/characters/writing - I found it tedious and kind of dumb.
- I disliked the three body problem for similar reasons.