It can be. But if you always travel at the same times, or go occasionally at a popular time at a popular resort that has fixed weeks, it can be a godsend.And me tempted to get FW 39 instead of no FW at all!
I've yet to be convinced that a FW is not a total PITA!
We always go in early December. Getting into either Wilderness Lodge was always difficult. But we have a fixed week for a shower studio at Copper Creek. Now the reservation just happens. No walking. No stressing. And since we got it the premium has fallen from 10% to about 3% with point chart adjustments.
The painful parts: dealing with member services to cancel, or dealing with member services to make any changes to that reservation, including adding or changing guests. And as I referenced, recently another issue is not seeing the reservation being made until quite late. For many years, the reservation for the following year was made while we were there on the current year’s reservation.
We love it. But we are creatures of habit. For folks like that it is wonderful. Others should really consider the possible PITA downsides you referenced. I do think that for sales restricted properties, the Riviera, the Cabins, and Lakeside Lodge (?), it could be a positive on your resale if you select a popular room type at a popular time to go, even if you never use it and always opt out yourself.