I have been active in these user-to-user Apple Support Communities for iPhone since 2007. I have never seen a post from anyone reporting that symptom in those 19 years. I have never seen a post from anyone who updated to 26.1 reporting that symptom. Not only has it never been a requirement, there is no way to make it a requirement except possibly through Parental Controls or device management by a business or school, and I’ve never seen it from anyone with a managed device either. There is no way to turn it off because there is no way to turn it on. So this is a problem unique to your, not to 1.5 billion other users.
What I suggest is to do a forced restart of your iPhone (you will not lose any data), if that doesn’t resolve it restore your iPhone from a backup.
But even before you do that, update your iPhone to the current latest version.
And if none of these resolve it contact Apple Support.
Best way:
- Install the Apple Support app on your iPhone or iPad - you can contact support directly from the app, and the tech will have (with your permission) access to diagnostic data on your device
Other options:
(Note that both of the above have options to receive a callback or chat)
Forced Restart:
- Press and quickly release the volume up button.
- Press and quickly release the volume down button.
- Press and hold the side button until you see the Apple logo (this might take longer than 10 seconds).

The operative word here is QUICKLY for the first two buttons, then a long hold for the SIDE button; and try it a couple of times, the timing is a little tricky. If done correctly this will always work unless the phone has a hardware problem.