Cell phones and other anachronisms
There is a scene where the prosecution team are in a bar, then one of them gets a call from a cell phone. It was a clunky phone with an antenna which were around in the 1990s but still not widely seen or used. People with jobs like that were more likely to have a pager then use a nearby pay phone to follow up on urgent pages.
Then in S1 episode 7 they arrest two computer geeks who “run a website”. Did they work for CERN? Who was running websites out of off campus apartments in the early ‘90s?
Also some of the slang and banter seem much more 2020 than 1990s.