This is a straight up devaluation of this level of the program. Not only were the Plt Extras a nice incremental reminder of loyalty, they provided an incentive for an extra stay or two. The ability to redeem the award for points (recently, easy to do on-line) became a nice way to ease the loss of G bonuses.
I am offended by Hyatt's logic. Because "more than 75% of the awards earned by Platinum members were never redeemed" speaks more to how cumbersome it was to redeem the Platinum Extras for anything other than extra points. So, therefore, Hyatt is saying "because we made these benefits so difficult to redeem, we are going to discontinue them and you won't miss them."
I wish Hyatt success in its obsession with the credit card product, to the detriment of the traditional component of its frequent guest program.