There must be magical cryptographic reason why CT doesn't create an UTXO. If it did make an UTXO, it'd be trivial to calculate the input + output right?
In Confidential Transactions (as used in Blockstream's Elements and Liquid), there are still identifiable UTXOs.
The only change is that instead of the amount, a homomorphic commitment to the amount is stored. While not technically correct, you could see it as a form of encryption that is compatible with addition and subtraction. So if a+b=c+d then E(a)+E(b)=E(c)+E(d) (where E() is the encryption function). This lets the verifiers still ascertain that the amounts in input and outputs match up.