Moral affects so many area's of the game.
- Results (Good luck trying to win a title when the whole dressing room is against you)
- Training ratings and as a result, player development (A unhappy player often gets lower training ratings which results in slower development or even regression.)
My advice is that before calling something an "issue" based on some (personal opinion: hillarious tests without even watched them), make your own experiences and take those "tests" with a pinch (or a whole bag) of salt.
Usually, the own gut feeling is a better indicator anyway.
Those are my 2 cents