and the people who do still download, wouldn’t care about doing it while on battery

Very much this; I've got a whole army of machines I can SSH into to launch a long-running download, which frequently additionaly cuts out a 2nd step of copying the file to where it needs to be after downloading it (a action which would normally cause additional battery usage on the laptop).

And I thoroughly agree with you; I want the laptop to go to S3 sleep immediately when I shut the lid, and then pull it out of my bag a hours later with only a couple of percent of the battery consumed in the interim.