My garage is half full for the same reason. Resale of most bikes over 3 or so years old is sadly the square root of feckall.

(Even worse on MTBs unless you have some really retro cool machine hiding away from 1987).

Only ones to buck that trend is the Brompton folder (as they are not much changed over 15+ years, amd are SO well designed) ? And the offspring's outgrown IslaBikes.