I've wondered about this. Not uncommon in mags that arrive from various mamberships. All I can do is turn over the page and think 'if they wanted me to read it they'd have made it readable.'
I did pass the Isihara? colour blindness test donkeys ago before being an electrical engr.
Page layout can be a problem too. Items competing for attention so you can't concentrate on any. A reporter friend years ago explained how subeditors grade items and lay them out so this doesn't happen. Perhaps as everyone does their own thing now on screens this expertise has been lost.