Many in game functions are already being nerfed, there got to be other solutions to reduce. As a solution to get around the slower dispensers is to add more.
I agree with this statement however there needs to be a balance between what is nerfed and how playable the server is. Currently this balance is tipping towards the unplayable side and something needs to be done. Many nerfs in place shouldn't apply anymore due to the introduction of a redstone limit (dropper pork nerf, hopper limit, spawner limit?, sell all cooldown) so perhaps the whole list of nerfed mechanics need an overhaul.
When these updates were in place was a large contributor to lag these water ticking? Iirc back when this change was in place tps was solid 18-20
Whenever water/lava is placed, it also updates lighting around it. So if someone were to have a machine that would rapidly dispense water/lava, it could potentially cause latency. It did show up from time to time but nothing significant and only a minimal impact when we delayed it (which wasn't worth the annoyance of dispensers sometimes not dispensing).
I do recall dispensers being changed a 3-5 months ago, but i dont recall it being an official part of any formal update, am i mistaken? I do remember it being a confusing time for me, i couldn't work out what the issue was with my mob grinder and as such moved on from using it for income/materials, Would it be worth attempting this update again but with times on cooldown shared for user ease? Also not sure if im just a derp or am missing something but if a mob grinder is a blackout area, how does the water flowing cause lighting to change? Are we sure its not the state changing/water flowing of all the water at the same time that could be the resource hog in these mob grinders?