I've worked for both. I have seen massive waste in business, millions spent for no gain, staff employed to build a manager's empire, not to do anything that was actually needed and other terrible outcomes. Obviously that also happens in government too, although the bigger problem there was a whole bunch of lazy staff who were hard to fire.
But... A business can largely choose its market and optimise for that. A government cannot - it has to work for pretty much everyone. Business can choose to skirt the law or even break it. Government departments must comply with all law to the best of their ability.
Not saying there are no ways to improve government efficiency. But the people who think you just need a business approach (unless you just want to break it all) are deluded.