@puzzlezaddict tried that twice, both times unsuccessful :/
the EA app does load, and at first I tried to play Sims on EA app, though as previously mentioned I couldn't access my DLCs, which despite being a flaw I believe isn't an actual bug/issue.
I've had other issues with the EA app in the past, but recently it's actually been working for me well, so I think this is a Steam-EA problem.
I've just tried to sign into the EA app with Steam credentials and it says 'You must be online when logging in for the first time.'
which is weird, because if it means Steam, I'm logged in and online, and if it means internet, I am also.. online?