"with no mention of it being AI-generated" is the problem.
I use AI sumerization and translation in my products. It is not a problem as users are aware of that and the consequences that might have in terms of errors, and behave accordingly.
And in any case, replacing the subject line with a summary, is an absolutely insane thing to do. If it were an addition to the subject line? Sure. But replacing it is madness.
In my case it works as the users are experts in their fields and thus (a) can spot errors quickly and (b) use the system as an information shortcut but never act without extensive verification with the full source.
If they can spot errors quickly (which implies they're reading the original anyway, since how do you spot errors otherwise), what is the benefit of the summaries to begin with?
It answers the question 'which of these 100's of new articles and publications produced in the last few hours in 24 languages should I look into today.
This is in very niche domains, so a 'that is probably not realy correct' stands out like a sore thumb.
I use AI sumerization and translation in my products. It is not a problem as users are aware of that and the consequences that might have in terms of errors, and behave accordingly.
Still saves them boatloads of time each day.