Thing is, these aren't GONE. They aren't dead, buried, etc.- they're just archived. Want a Shootist? Get a Shootist! Hell, get a few, minimize the archive fee since it's for only the first one. Never mind the fact that IWM frequently does the month-long return from the archive every so often.
Shootists, Jagermechs, etc. are staples, yes- of Inner Sphere armies. But, if it's being mentioned here, that means it's not SELLING WELL for IWM- they don't care about whether Davion or Liao or whomever uses a design frequently, and they shouldn't have to care. They're looking at their business- and if Jagermechs aren't selling, then off to archive they go. Nothing difficult about this, no evil cabal out to ruin things for you, just business decisions- and at the end of the day, wise ones.
(That said, I did give a vote to the Flea since I was thinking about getting another one in my summer order. ;) )