.... commercially released music will be automatically "leveled" so that making a louder mix will be irrelevant.
The article that the OP linked to is vague, to say the least. If you want to know more about the subject, and why it's in the air, so to speak, visit SOS's website and search for February 2014's "The End Of The Loudness War".
The "end" of the war and what you are referring to from last year has to do with the iTunes streaming codes that now "level" everything to a set standard, and that is something that is slowly spreading to other streaming outlets....so that's why that article called it the "end" of the loudness war.
The Sweetwater blurb is referring to something esle...saying that artists/engineers are also starting to back off on the digital loudness, has claiming that the war is "over" 'cuz people are not trying to fight it anymore. They do it either because they are now hearing things differently, or because of the fact that their streamed music will now be leveled anyway, no matter how much loudness they put into it...hard to say which, or if it's both.
One thing that was stated about the streaming "levelers", is that because of them, if you now tried to pump up your loudness to extreme limits during mixing/mastering, it would sound worse post-levelers than if you made the levels more reasonable during mixing/mastering.
Of course...that applies to streaming. So, you can still jack up your levels as much as you want without any issues, just don't send the MP3s to iTunes.
I just find the whole thing rather funny and even cyclical...and I'm sure there will be more technology changes to follow.
I mix the way I mix, at the levels that sound good to me....not wimpy, and not crazy loud.
There's still a lot of room for many tastes...so not much to really worry about AFA "loudness".