In fairness to him, those within journalism would very much consider editor a journalism role. just as they would include photo journalist, newscaster, reported, investigative journalist, copy writer. etc..
I see no basis whatever for this assertion - unless this consideration were being applied simply to minor matters like membership of NUJ.
When last did a photo-journalist get made an editor of anything other than something like a heavily illustrated magazine, e.g. Paris Match ? Are we to expect High Court challenges by copy writers passed over for the position of Editor of the Irish Times despite their 20+ years of sterling service writing puffy house for sale ads ? Newscasters of recent years have been allowed to interview some of the subjects of news stories. But their inexperience - and moreover their lack of natural aptitude - for this task is usually quite evident. It gets them out of the studio for a while - and it gives overworked reporters a rest reading the news - but it's not something that produces worthy reporting or incisive questioning on the part of a newscaster, whose job is principally presenting the news in a suitable way.
I take your point of a need to make a fresh start with an outsider. But such is the scope in the present appointment for a lot of people in RTE to turn this restructuring into an England v Ireland scenario in the minds of other RTE staff that it is an almost impossibly hard job for the new DG. Things might be easier were the new DG be given freedom to select some respected outsiders (Irish as well as EU) to include in his various divisional advisory committees.