Of course it is, it's long overdue, I've never understood why there is no 5th set TB when there are TB's for all the other sets, makes no sense, plus it's insane on the players, whoever invented no TB in the 5th was mad.
You've got it the wrong way round. Noone "invented no TB in the 5th". In AO, FO and W there has never ever been a 5th set TB. The invention was TB in the 1st through 4th.
Please. Whose fault is it that one player uses their talent/skill/experience etc etc to close out a match sooner than someone else who lacks the killer instinct to do the same? A tie breaker is a ridiculous throw of the dice. The last set should never be decided on such a lottery basis. If anything they should introduce the long set in the BO3 matches.
why the middle sets are decided by TBs then?
It's the same reasoning for all of them - either you have a separator, or you let them play until someone dies.