This is a reason why it shouldn't be updated.I don't think most people are going to like it is going to cause to much problems.Like it can cause lots of more lag you don't own a good computer or a old/new one then your probably going to have problems.The update is going to be really big and going to bring lots of things.It would be good that it can stay the way it is right now.So you can keep it to 1.8.9 or less no 1.9 please to much lag.So you can now see its not good.
Mineverse is a heavily pvp sever. 1.9 kills pvp, who wants to pvp with a SHEILD or COOLDOWNS when hitting. Like honestly it's just terrible.
It already has been, or it's 1.9 compatible. If you do not wish to use the 1.9 update, I believe you still have the option to use 1.8.9. Use it (if you can) while it's available :P
Minecraft was created by Notch, Notch's first Idea was to make the game Minecraft: Order of the stone. This would be a blocky RPG Game. That is how minecraft is becoming now, the way it was meant to be at the beginning. If you don't like it, then I'm afraid you will just have to leave. Even though myself and others think that 1.9 and the future updates will most likely be horrible, Minecraft wasn't made for PvP.
The main reason why minecraft is so enjoyable is that is was so simple, now they are just making it complicated. It's minecraft not Dota.