Another vote for Greg Egan. And I too really enjoyed the Children of Time series and anything written by Alastair Reynolds, although I don't think the genre is exactly what you're looking for. Finding modern, hard sci-fi really is pretty difficult.
I get where you're coming from with KSR's Mars series. I think Ministry for the Future was a better read, personally.
Also, I find that a lot of Crichton scratches similar itch to Andy Weir. Especially things like Andromeda Strain and Airframe.
I appreciate you taking the time to respond and express your views, especially knowing what the response would probably be. Diversity of opinion is always important.
One of the communities I miss from reddit is r/ZeroWaste