I have different experience. Having USB-A to USB-C in the path leads in my experience to better results and both negotiations and measurements above 0,5 A.
See:
My interpretation is that when having USB-C to USB-C you might come to problems in the negotiations and end up with 5V 0,5A, while with USB-A in the path it falls back most likely to BC 1.2 which is up to 5V 2A for our case.