I am constantly connected to my VPN at home if my iPhone is not connected to a WiFi in white list, and I use an IP white list, including DNS, to go through the tunnel and I play no adware games 😂I guess that is why it works so well for me.

But nice to know why VPN on phone behaves like it does if you route everything through it. I think have experienced that before, when I forgot to disable the third party VPN I use to spoof location.