Press chiefs could be so tired (7)
I believe the answer is:
editors
'press chiefs' is the definition.
The definition and answer can be both people as well as being plural nouns.
Maybe they are linked in a way I don't understand?
'could be so tired' is the wordplay.
'could be' is an anagram indicator.
'so'+'tired'='sotired'
'sotired' is an anagram of 'EDITORS'.
Can you help me to learn more?
(Other definitions for editors that I've seen before include "Employees on paper" , "Newspaper heads" , "Newspaper bosses" , "Senior journalists" , "Press employees" .)