ok so here's a short list why
-more expansive map
-more events that happen every once in a while, and special varients attached to them
-most infected have special passives or abilities
-there's a wider range of infected variants, providing a more colorful game
-the mechanics actually work
-more weapons and weapon skins
-better models
-has f**king lore, maybe not a lot of it, but it's better than nothing
-not pay to win
-infected models actually give a shit and look decent, they also have face expressions instead of the same boring roblox face
-the map doesn't reset every 4 f**king minutes
and
that's a few of them