No ROBLOX game is approaching the amount of resources Skyrim used, even if it's an eight-year-old game. Regardless of what the average system RAM is now, there's no ROBLOX game to use it. Copy+pasting a chart doesn't magically change that.
Might be a good idea to read what you copy+paste. Note the title mentions modding, and the paragraph after the bit you quoted is as follows:
“We present this information with the hope that modders/mod authors will keep these limitations in mind when using/creating mods, especially texture-heavy ones ...”
As I mentioned earlier, 4GB is plenty for vanilla Skyrim. It only becomes a problem with heavily-modded installs. ROBLOX games aren't close to vanilla Skyrim in terms of resource usage, mess less heavily-modded Skyrim.
Copypasta from the internet doesn't contribute to the discussion. You may consider taking up my suggestion earlier and researching what you post.