A position they held steadfast to when newspapers unionized and it became the norm. Their reliance on surprisingly young journalists (kind of like consultancy bodyshops that recruit out of uni) is one reason they were able to avoid them.

Newspapers have often been threatened by their more popular contributors leaving and taking subscribers with them.

They'd therefore never introduce bylines if they had the leverage relative to their journalists to avoid it just as McDonalds wouldnt offer free daycare if it werent struggling to hire and tech wouldnt offer free food and lavish comps.

>Your point--that reporting shouldn't be primarily about individual credibility

That doesnt seem like a point I would ever make.

I mean, you can justify it "in principle" however you like, the economics boil down to the relative leverage of management and journalists. Bylines function as an asset (reputation) that journalists can, in a sense, capitalize and gives them the leverage to take subscribers elsewhere allowing them to negotiate a greater share of the newspaper revenue (lowering profits).