Backwards Compatibility has been broken since the start of its release. Multiplayer is essentially broken on all games using their own servers. Help #FixBackCompat by sharing these videos around the communities who play old games.
If you Tweet at these people make sure to use #FixBackCompat and link the video at the top.
Also, feel free to tweet at Tom Warren, the senior editor of The Verge. His DMs are open and he's always looking for tips. If a lot of people DM him about the same situation he'll have no excuse to not write about it.