How to turn off "Found In Natural Language" in iCal Calendar for iOS
I saw someone post this question here: https://discussions.apple.com/thread/8502424, and it seems Apple doesn't like it if someone does not quickly respond. Quite ridiculous Apple, that after one of your customers takes the time to post a question here that you would lock the discussion and not let anyone respond just because that response didn't happen over night.
Anyhow, enough of the ranting... The solution I found to permanently stop the "Found In Natural Language" calendar to show up in iCal (and obviously stopping iOS from harvesting all of that data so it can 'conveniently' offer it up as an iCal event) is this:
Settings > Siri & Search > scroll down and find the preferences for 'Calendar' > deselect 'Find Events in Other Apps'
And, while you are at these Siri & Search settings, feel free to deselect as much as you want. And also notice how much data that Siri & Search is collecting for your 'convenience' from every app on your phone. I have opted to turn as much of these 'off' as possible and am happy to be a little inconvenienced knowing a little less data us being harvested from my usage than the buckets that already are.
(More big picture existential perspective sharing...) It seems not too long with my / our lifetime, it was inconceivable to allow such an invasion of so much personal information with such lack of care or concern just for the sake of convenience in using a device that gives us instant access to whatever we want. I feel the trade off of all of the convenience in our modern wold is creating a great great burden on our human family that we almost have to go number too as it is an immense price to pay for the impact it has on us and will continue to have on so many levels for generations to come.