Doctors don't want the blame or the purse strings, because, well, under Labour GP's have become, or been able to become incredibly rich while providing worse and worse care basically.
As for saying doctors aren't overpaid, a lot of doctors aren't, GP's are MASSIVELY overpaid, and they are underqualified as doctors, you go into an ER and find a doctor who can diagnose just about anything, perform emergency surgery and hundreds of procedures, a GP can barely do anything these days, you can get a doc who hasn't performed a procedure on a patient in 40 years and hasn't seen a wide range of cases in decades either.
GP's are already heavy paperwork people, they essentially run businesses as is, many MANY doctors in hospitals go on to management roles with never actual training, thats what happens in most industries, many many gp's are on boards, and various planning commities, there is plenty of experience there as GP's/doctors have been involved in the planning side of the NHS for decades.
The NHS needs reform, does it need THIS reform, maybe not, and doing something rather than doing nothing isn't always the right option.
But GP's at some stage will have to account for getting more money for hitting targets, while patients all complain about lack of time with doctors, serious conditions being missed and the inability to get a real appointment at short notice. The public won't accept GP's current excuses of "its the system, its not our fault", because they'll be the system.