Get out of old technology (4)
I believe the answer is:
exit
'get out' is the definition.
(I know that get out can be written as exit)
'old technology' is the wordplay.
'old' becomes 'ex' (prefix meaning former or onetime).
'technology' becomes 'IT' (Information Technology).
'ex'+'it'='EXIT'
'of' is the link.
(Other definitions for exit that I've seen before include "Leave the building" , "walk away" , "Relinquish the lead" , "Act of going out" , "Escape route?" .)