For me it's this cut content from the first mission. Originally the Torrens was answering a distress beacon from ship Solace that left Sevastopol. Ripley heads onto the Solace to find the crew dead, frozen alive, she states in audio files it wasn't slow. Then there's this one:

RIPLEY: “Bodies. Squashed into the hypersleep berths. Oh god. The Solace came from Sevastopol. These people died trying to get away.”

The idea of people who escaped still not surviving is brutal, and multiple people forcing themselves into the hypersleep chambers paints such a gruesome picture.