That's so true. My spreadsheets are computed in today's dollars, for the same reasons. Even though I know that my money will be losing value, it is less confusing and simpler for me to convert everything to today's dollars.
Increasing my "allowance" to myself each year may seem (to me) to be an act of breathtaking bravery and daring, but I will need to do that to compensate for inflation. What a rush.
Maybe after ER I will create a set of spreadsheets that are not in today's dollars, since my financial plan will be in place and fixed at that point.