When did Apple first launch the iPad and you still can configure it for multiple users? How can they keep on promoting it as a laptop replacement when you can even switch between users? Perhaps that's what they need to 'fix' which would get around the Sidecar issue.
Apple like to sell control as 'security and privacy' but just how secure and private do we think everything is given nothing works anymore with data being checked in the cloud. Getting my Macbook and iPad working together inside my secure network shouldn't need to check anything outside it!
That’s just it: Sidecar
doesn’t use your secure network. It doesn’t use a network at all. Instead, it uses bluetooth and wifi chips to create a connection that exists outside your network - which allows you to use Sidecar anywhere - like in a park or a coffee shop. It’s really great - you can use Sidecar as a second monitor without the need for wifi (unlike Astropad or Luna). Apple is using Apple ID instead of the network to provide a one-click connection mechanism. Not relying on Apple ID would require some sort of authentication on both devices, which would make the process less seamless. The same method is used for switching AirPods between devices you own (they all have to be on the same Apple ID, but the result is that you can do it with just one click/tap). There are downsides to this system (as with everything), for sure, but considering the alternatives, it’s probably the best option. And it works really amazing, you just point on the green button on the window and choose to move it to your iPad - and woosh - it just appears there. Even the screen turns on.
As for multi-user support on iPads, I agree it’s overdue, but I’m sure Apple is working on it. It’s taking them a lot of time, but I’m guessing there are a lot of things happening behind the screen that makes this quite complicated. Just imagine millions of iPads loosing data or having security leaks just because they didn’t do it right. This may solve your problem, then you could log into the iPad with your Apple ID.
Either way, if you can’t appreciate the flawless execution of features like Sidecar, shared clipboard, Continuity, Handoff, etc. - and I do mean this honestly, we all care about different things - then perhaps you should look into the competition. They too have downsides, so beware.
For me, Sidecar is executed so great, I don’t see a better option for me, currently, because I’m not sold on Windows hybrids. But hey, perhaps you’d enjoy a Surface more, and the latest Pro X really looks nice.
They're running iPad OS 13.1.2 and macOS 15.0
