Indeed the suggestions (although annoying that we have to look for such things) are following the steps which are mentioned in the ''How to Completely Disable OTA Updates on iPhone or iPad" when you Google it.
I do get that for security reasons updating to the latest version can be good as far as security is concerned if there are serious bugs in an older version, however especially now with iOS11 Apple has seriously crippled a lot of things:
- no longer a 2 column widget view on iPad, you have to scroll to see them all
- no longer the option to fully turn off WIFI or Bluetooth within Control Center directly
- no longer allowed to use URL schemes for Apple's Settings app or various Apple apps to quickly launch things (see
Launcher topic and
this one). I know the new Control Center has some options now which iOS10 and before didn't have but it still lacks quite a few things. You can't go quickly to Settings such as 'Refresh in background', 'Location use per app', 'Notifications on apps' 'x amount of MB/GB Storage per app', Battery status (x hour of usage/standby) and Storage maintenance that are unfortunately missing in the list of options to see in the new Control Center and you can also no longer launch other various Apple apps.
It's also so odd that in iOS11 you no longer can turn off WIFI and Bluetooth within Control Center see
this.
Aside of updating to a newer iOS version could really slow down older iDevices such an iPhone 5s, iPad mini2.