A software update is required to connect iPad.

Hi there uli_d,

If you are seeing this message when you connect your iPad to your Mac, it means that the software of your Mac needs to be updated in order to support the newer software you have installed on your iPad.

The only way to remove this message would be to update your macOS. If you decide you would like to update in the future, ensure you follow these steps from Update macOS on Mac to back up and update:

Before installing new software, it's a good idea to back up your Mac.

To check for new software, open Software Update. It's in System Settings (or System Preferences), which you can open from the Apple menu  in the corner of your screen:

* Choose Apple menu  > System Settings. Click General on the left side of the System Settings window, then click Software Update on the right.

* Or choose Apple menu  > System Preferences, then click Software Update.

If Software Update finds new software, click the button to install it, then enter your administrator password when prompted. During installation, your Mac might show a progress bar or blank screen several times, and you should avoid putting it to sleep or closing its lid.

Take care.

I don't find this at all helpful - here's why. If you ignore the message, in most cases, your connection between the iPad and Macbook will continue to work just fine. The message is intended to get people to update their Macbooks when it may be disadvantageous to do so. I'm not impressed with this tactic or the lack of an option to revert to an earlier version of system. Apple/Cook really needs to stop disrespecting customers like this. I'm now stuck in an update that will take an hour of my time (per the notice) and I'm now one premature step towards obsolescence.