In 2011, my husband had 8 inches of colon resected to remove a cancerous tumour, in an NHS hospital. He spent two nights in hospital and was discharged on the morning of the third day. (He was on a rapid discharge programme.) He could eat and drink OK; he could just about get upstairs to bed, but we had to cobble together a rope pully to get him in and out of bed, as sitting up was painful and difficult for him. He could barely walk for the first few days. I provided all his care in the coming days apart from one visit from a district nurse to check his dressing.
I had complex hip replacement done in a UK private hospital in late 2022 (self-funded). I was booked for at least two nights stay (though my surgeon does sometimes do hip replacements as day cases under spinal block, which I had in preference to GA, within the NHS and when working privately). I could have done with at least one additional night in hospital as I was so tired. But I was deemed fit enough to be discharged on the morning of day 3, post-op, as I could sit on a perching stool to wash without help, could manage the toilet without help, could walk with crutches, was able to do a few stairs, my incision wasn't leaking and my pain under control. I paid a little under £15K for a surgical package which included a number of post-op physio sessions and a couple of follow up clinical and consultant appointments.
Had I wanted to spend additional nights in hospital, I would have been charged extra for the room, meals and nursing care over an above the £15K package as I was deemed well enough to return home. So unless you can afford to pay extra (or your medical insurance pays for extra days), you don't always get longer to recover in a private hospital than you would in the NHS. One of the non nursing qualified health care staff told me they were being paid minimum wage rates.