>>Old people can see that, but it requires looking with fresh eyes, as opposed to only being willing to see what was there decades ago.
The controversy arises from the structure of the sentence. It implies that 'looking with fresh eyes' is the rare thing, and the common thing is that older people are "only being willing to see what was there decades ago."
Sure, you technically acknowledged that it was possible, but the sentence structure guides the reader to conclude that your view is that old people only see the old stuff, thereby treating them as a monolithic unit, and thus ageist.
I've often had this sort of issue myself. I've found the only thing that helps is merciless self-editing, and keeping in mind two things.
First is a passing comment from a professional writer friend who was weighing how our choice of allocating more words or fewer gave different weight to each concept we were trying to get across in a short piece we were writing, saying something like "using that many words here gives it too much weight".
The second thing I've found often useful is to put the key concept and a key word at the end of the sentence and paragraph, where it is actually most punchy and emphatic. The beginning is second best, and the middle just buries it.
I notice that you sentence buried the 'fresh eyes' concept in the middle, and used a much longer ending phrase ending in 'decades ago', so compared to your intent stated here, the emphasis was kind of backwards.
Perhaps better would have been "Old people can see that, and although everyone's tendency to see just what they already know, they'll see the new opportunities just as well as anyone else when they make the effort to see with fresh eyes.".
