It's only one wing per week that get the "infantile mode". At best they make 16 golds (W4, 4 encounters, double gold).
Raids are often seen as scary and elitist by many players who never raided. For some of them, spending a few hours in a training without a kill is a waste of them.
By turning the difficulty down for training groups for ONE wing per week will make these players more susceptible to join trainings because they have greater chance to see a kill.
Many raiders I know complain about "raids being dead and not enough new players participating". This change should attract more "casuals" (used as a contrast to the OP's "hardcore") into the raids, which I think will be a good thing for the community.
Maybe some of these players will be like "oh this was fun, raids aren't so bad! I should learn other wings too!" And they will gradually become a more knowledgeable player in raids.
Besides, everyone starts somewhere — these new players getting rewards should not influence you in any way