Just detaxed af CDG terminal 1 (T1) for a united flight leaving very early. I had read so many posts about extremely long waits that I got to the airport 3 hrs early, at 6 am and there was NO LINE. It took me literally 1 minute. I think it being a United-only flight probably helps to keep the traffic low. It was empty when I strolled by at 5 pm the night before as well (I was staying in airport hotel). It’s also very easy to find in T1!
A few times I've stayed in airport hotel and did the detaxe the night before. Technically you aren't supposed to but if the forms don't reject it works (and sometimes even if you have to see an agent they will process anyway) so its definitely worth a try.