It significantly increases tournament ticket revenues, as there are more days of play. This in turn enables them to pay the players more in prize money.
The higher ranked players seem to universally dislike the change, but I suspect they want to have their cake and eat it too i.e. they want to keep the extra prize money that the longer format enables.
No one ever asks the lower ranked players, but the 96 player draws do give more players the opportunity to play Masters. However, as all the seeded players get first round byes, the early rounds feel like an extended qualifying tournament.