You can still face 2 WoD and lose if you don't draw your Cyclone out on turn 2. Trunade can get rid of all backrows and OTK on turn 2 but it will not exist after today. Set 3 and end turn 1 will be a common move, a single Cyclone won't save you from Karma Cut + Floodgate + WoD.
No, someone has to be very bad at the game to lose to wall of d. It's easy to know when you are facing a battle trap and most deck nowadays can destroy cards before going into battle phase.
If for some reason you deck can't destroy cards and you see you opp hasn't chained their backrow then you switch 1 of your monsters to def
Yes you can destroy 1 or 2 traps before going into battle phase but can you deal with 3 backrows on your turn 2 without Trunade? People who rely too much on Trunade will face the reality now.
Yes. For any deck that is not shiranui opening 3 traps is a brick, if for some du mb reason I attack into an obvious battle trap I still keep most of my monsters + whatever backrow I opened while opp is in top deck mode, I can just spam my backrow and use my weakened monster for some extra deck play next turn.
If opp had non battle traps instead I could have never settle my field to begin with