I highly doubt the Jets do any scorched earth rebuild and sell everyone off (this summer), to be clear OP isn't suggesting that. The pieces in the OP are just the expiring contracts of vets, I doubt all would be traded. Trade the high value ones, keep a couple vets with lower value for leadership (they can be traded at TDL the year their contract expires if desired). Highly doubt a Ehlers or KC would be traded (at this stage/summer), they still have some term.
PLD/Mark/Helle should all be traded assuming Mark & Helle don't want to resign this summer. PLD will be traded this summer. The return just from those three guys would speed up any restructure. Some of the other pieces in the OP can also be traded (this summer or next TDL) but the three big ones are Mark, Helle and PLD.
Just like other teams have done, tank for a 2-3 years and then develop all those young players into/towards a competitive team. Posters asking if the Jets "can or should" rebuild/restructure is a moot point, all teams have to rebuild/restructure at some point, rebuilds/restructures are like death & taxes, can't avoid them. Ownership knows this, attendance will suffer for 2-3 years, not unlike other teams rebuilding and ownership is ready for that.......to suggest ownership can't afford or hasn't planned for a rebuild (at some stage) is silly, of course they know its coming, its just a matter of when.