I used Charles proxy (basically a "man-in-the-middle") to monitor the network requests and the data transmitted.

Also, some iOS apps support running on an Apple Silicon Mac (with M1/2) and, in a similar fashion, one can use various apps to block or inspect the network traffic.

Yes, it's a bit more work - hence my complaint about doing free work for a ~$3 trillion company - but I like to know what data the apps I'm running are sending home.

I know I'm a bit paranoid but hey, we all have issues, right ...right? :)