He only played when Carvajal is injured or suspended because Carvajal is a beast.
He did well prior to Real and Barca were after him before so it tells you how good he was before the move.
Personally, I wouldve kept Maffeo and built him up. Walker 1st choice, Maffeo as no2. Mendy left side with Angelino or A.N.Other promising kid as no2. Walker and Danilo have pretty much blocked Maffeo's rise up to the first team now. Both are at ages where they can be part of City for their contract and maybe a few years longer which means Maffeo is screwed for half a decade tbh. Looks like he will be sold on or the weaker on of the new RBs will at a minimum.
Not that he's had the greatest opportunities but I don't think Angelino is good enough as a left back. He should move further up and play left mid