So the nutritionist gave you a window that included more protein than you were originally targeting?
Protein is 4g per gram, so the higher amount is about 25% of my calories, which is between the 10% to 35% the Mayo Clinic suggests.
I am physically active so that requires more protein especially before and after strength training.
It was also recommended to limit protein at one meal to about 45g, which was hard to do with a 7-hour intermittent fasting eating window, so I’m now using about a 10-hour window.
On the other side, one to three times a year, I do a 5-day Fasting Mimicking Diet where among other things protein goes to less than 16g per day.
There’s probably, or ought to be, a book on nutrition for older people. For example, vitamin D production from sunlight goes down, as does B12 absorption. 60% of the elderly are B12 deficient. Of course the low vitamin D was a PRIMARY cause of the scamdemic.