Simple answer.
Like global warming, there are lots of people who have a vested interest in this not being a real issue. Unlike global warming it would be a simple matter for the industry to get serious about some conclusive tests. They don't.
I've never been affected (to my knowledge) but now know a couple of people who are sure they have been & saner more balanced types I've yet to meet. What disturbs me is that there has been stock answer statements put out by those who are charged with our safety & regulation - and this includes manufacturers, pilot's union etc - for a very long time now.
The consequences of there being something serious in this are very big & where big consequences exist you usually find plenty of resources devoted to denial.
There will be many pax who are affected but have no idea how/when/by what or even what they have. Engine oil contains organophosphates - fact. It's a poison - developed by the Nazis to kill people - so go figure. How good are your oil seals??
What does seem to come out if you read these articles or saw Panorama is that most are not affected but some are and very badly. It needs looking at pronto before a crew becomes incap & kills a lot of people.