Hi Nicolò good question! In terms of the contributions this calculation has monthly contributions increasing for inflation each year. In terms of the impacts of inflation on what a million dollars can buy you, no doubt a million bucks in several decades isn’t going to be worth what a million bucks is today.
BUT if you assume rather than a 7% total return, your investments average 7% above inflation then the math works out the same to arrive at a present value of $1 million by the time you reach 65.