It matters because (in an unbacked monetary system) there needs to be consensus between the participating parties that the blockchain state was altered and the nature of that alteration. For there to be consensus, that state change needs to be reported consistently to all concerned. Doesn't matter if it's "balances" or transaction ID's or what.
Wtf... This is exactly what monero does. Just because an outside observer can not know the balance of a given address or which address has interacted with which doesn't mean it lacks "consensus on the blockchain state was altered and the nature of that alteration." It wouldnt even work if it didn't accomplish this.
We all need to be looking at exactly the same information
Ok well everyone does look at the same information but I suppose not everyone has access to the same data.
and have access to the same data, even though altering it may be a privileged action.
For certain applications maybe. For other applications that is terribly undesirable. Do you think someone on the dark net wants everyone to be looking at their data? What about a corporation that needs to keep its information private from competitors.
The idea that such a trivially simple but commonly performed act of summing all the transaction outputs for a given random address should be limited to only 1 individual in the entire world who happens to have a private key to that address is ludicrous.
And thats not how monero works... It is limited to anyone who holds the private key or the view key. That could in theory be everyone in the world or only one person or a group of the private key holders choosing.
Not only that, the amount of work and programming involved in actually hiding this information is phenomenal because you're basically having to UNDO (conceptually at least) all the work that has already been done by the public-private key encryption that makes "the wonder" of a transparent blockchain possible in the first place.
This is false. The computational overhead is relatively negligible.
Look at what Cryptonote projects are doing. While everyone else is getting on with tooling up commercial interfaces, Android wallets, iPhone wallets, API's commercial gateways and diverse gateways, Cryptonote has it all to do on the blockchain protocol. And for what ? To make a blockchain thats less transparent, less auditable, more open to confidence scams and far higher maintenance than bitcoin ?
For privacy. Privacy is valuable to a lot of people. And it doesn't have far higher maintenance. It has marginally higher maintenance.
You are extremely uninformed. Which is fine. I'm uninformed about roughly infinity more things than I'm informed about. That's the nature of life. But I don't go around spouting nonsense about the things which I am not informed about. You seem to understand bitcoin well enough but you should study monero more before you attempt to argue their relative merits.