That's good you're using articles to back up your claims and stance.

Oh dear.... they would need to rewrite their entire website for a digital audience! That is a tough obstacle.

I would hope that most of their readership, or direct traffic, is at a college reading level, but in order to attract search engine traffic and to keep that traffic on the site, it needs to be at an 8th grade reading level. People don't want to have to struggle to understand -- they want the content in simple language that is easy to scan and digest quickly. We have 2-3 seconds to capture search engine traffic's interest once they land on a site and a few seconds more to maintain their interest... you definitely have your work cut out for you there....

I wouldn't know what to advise since it's a large site and they probably won't want to rewrite it for a digital audience, but that is what I would probably end up proposing myself, regardless of whether they take me up on it. If most search engine traffic is bouncing off the site (ie, high bounce rate), then you have a partial argument for perhaps why that is happening. (((hugs)))