While it was called the “doc fix”, really that money went to hospitals, labs, pharma, etc. It would have had little impact on actual doctor salaries except perhaps doctor-owned clinics who liked to make extra cash by gouging the government.
Mind you, what it actually did was avoid the limits on rate increases year to year that were set in law designed to keep costs from spiraling out of control. Had they not passed the doc fix every year, Medicare would have spent about a couple trillion dollars less than it actually did.
Worse, Medicare rate schedules are used as a soft floor for hospitals when negotiating rates with private insurers so those rate increases rippled through to private insurance costs as well.
If you want a reason why your healthcare today is so expensive… the doc fix is at the top of the list.