yes, if you join a server you download tons of props and stuff, but you cant use these props when you play singleplayer and that is really annoying.
Possibly because that would install un-wanted models, have the ability to send viruses to others and would take alot more time.
You don’t actually get any props when you join unless they make you download them, and if you do get them. Then yes you can probably use them in singleplayer as well.
And if the file is listed when you join a server it might not download, but the game only requests it from the server and you won’t get anything. Meaning the file might not be on the FastDL or remote location.
And you can still send viruses to others anyways, just make lua add the resource to download off the server and you can still get viruses that way, Garrysmod does in no way block that.