I've read that Riot is considering reverting Zac's ultimate. I hope they won't, because it will remove skill from the champion and play-making potential.
The current ultimate requires thought and may back-fire if used in the wrong way. You cannot just press R and get a result, you need to land E and you need to consider if it is worth to use it. Moreover it's also thematically fitting and very satisfying to use.
The old ultimate, instead, was literally no-brain. There was no reason not to use it: you would use it everytime there was a fight for random and easy disruption. No need to put thought on it, because it also allowed Zac to use W (the main source of damage) and to collect blobs (great form of sustain) while active.
The old ultimate was toxic and brain-dead,
please Riot, reconsider your decision! If you want to buff zac, bring back some of his W's AP ratio, or give him some sort of resistance steroid when landing Q. I don't really know what could be the alternative, but I'm quite sure that reverting the ult will be a mistake