It's not the whole point though. If you believe there is no chance of playoffs either this year or next year, then yes you may as well trade everyone you can, and hope enough prospects come through (including ones you've acquired) so that we can compete again in 2020 and beyond. In that scenario you're only really wasting the 2019 season, in exchange for a bigger chance of succeeding in the future.
However, even if you think this season is already a write off (and IMO it's still too early for that), next season isn't a write off until we see if any of the existing prospects make it, and people like Travis and Pearce can be counted on. So for me, right now, it's not worth writing off 2018 and 2019 by trading everyone.