If the game had no difficult content then the goods would just leave, or they would still abandon the bads as there is still no incentive to carry them. The continued movement to smaller raid sizes in and of itself has decreased the incentive to carry players. Why carry bad players in a 25 man when a 10 man gives them same rewards and you can cut the chaff?
And if the goods raid for a challenge, then clearing everything on the first week because there was no difficult content would remove them from the game anyways.
Normal mode content is easily clearable by average players in a short time frame. Hard mode content can be approached by average players on a longer time frame, and by upper echelon players on a fairly rapid pace. Normal mode content is clearable by bad players on the same timeframe that hard mode content is cleared by average players.
The problem comes when bad players expect to clear hardmode content as quickly as average or upper echelon players.
Accept your limitations.