I disagree that it's about the graphics (in this specific case). That scene has a scare that, when looked at by itself, is not scary at all. However, the setup is so perfect that it had people screaming when they first watched it. I was definitely the target audience at the time, maybe 11 or 12 years old, but it was incredibly powerful. I still get goosebumps when I see it, even though the graphics are bad. It wasn't a jump scare; they flat-out said what was about to happen in more ways than one. But there was something so pure and fulfilling about them actually following through with exactly what you expected that it transcended being a simple scare.

Anyway, if you watched it as a kid there's a decent chance that scene permanently lives in your head. I believe that's what the poster is referencing.