I'm using an aging xiaomi phone with the older USB connector with charger, I also have a xiaomi hair clipper that included a USB-C cable, no actual brick. Even my 9 year old iPad outlet brick works with USB-C cable and can charge that 2020 USB-C hair clipper, my Mom's USB-C phone is also charged with that 9 year old Apple USB charger (not that it doesn't have one, it does, we just kept using the Apple one that was on the wall). So you don't have to buy a charger for your new iPhone, just the USB-C cable with an old charger.