The 5x11 scoring system proves that you need to be mentally tougher than the 21-point system as each game is now shortened.
You either regain your composure ASAP or lose it in the 5x11 system. In the 21-point system, you have time to regain your composure and close the gap.
The new scoring system also allows for less catching up, points wise. Previously, if you were, say, 6 points behind, it's possible to close up the gap and even it out and possibly taking the lead. In the new scoring system, such a wide gap is disastrous. The odds of losing the game is higher. When the next game starts, your opponent would probably have changed tactics on advice of his coach and you need to readjust, giving more room for errors.
Badminton will not only be physically tougher (I think we are going to look at quicker games looking at the duration of the matches), but also mentally tougher. If this scoring system is going to be permanent, guess we will be looking at upsets for quite some time while the players adjust to the new scoring system.