You can find your balance by looking at the UTXO set and seeing if your adress can spend it. There is no need to trace where those UTXO came from.

But every full node does, because it is required to validate the chain.

Near as I can tell, you just don’t know how Bitcoin actually works?

	▲	charcircuit 2 days ago \| parent [-]
		I will say it again. When validating the chain all it cares about is that the sum of the output UTXO for a transaction are <= the sum of the input UTXO. All the input UTXO are no longer valid once spent and can be forgotten.