They really, really don't. I have constant Bluetooth issues with all of my Apple devices, and since all of their flashy stuff relies on Bluetooth most of it breaks every couple of days.
Universal clipboard failures, AirDrop failures, AirPod pairing issues when trying to switch between devices, and total Bluetooth stack crashes.
They get things working to 80% and then just stop maintaining them.
I don't own any apple products so correct me if I'm wrong, but if there was a way to make a program to "just work" will Apple allow it? From what I've heard devs complain apple's walled garden is pretty restrictive when it comes to things you can and cannot do especially when mobile devices are involved.
Apple gear and software always has a low-level advantage, as they own the SDK, but I haven’t seen them actually use this to deliberately disadvantage competitors (unlike some other companies that I won’t mention).
That said, I have seen them “Sherlock” developers, though; where they implement integrated versions of products made by independent devs. This has been fairly controversial, as they have not always paid/given credit to the developers they plowed under. That sucks, because it would, literally, cost them nothing to simply mention the product that inspired their work. I suspect that’s because lawyers.
I tend to like Apple for the same reason that other developers hate them. That “walled garden” is a big fat PItA, but it is also the reason for an enormous, lucrative, market. We need to learn to take the bad with the good, if we want to be happy.
Try to write code for macOS that can stream data from disk as fast as Logic Pro. Maybe there's really no magic, and I'm just an idiot, but I certainly couldn't do it.
As an independent developer, I can certainly understand why I would not be allowed to access some of these private APIs, and I don't feel that it is because Apple is afraid of any competition from li'l ol' me. I have always assumed that it's because access at that level may bypass some security methods.
Listen, I'm not gonna play this game. I said my piece, you said yours, we're done.
This walled garden is 100% a feature.
It's a pretty niche feature. I have used both Barrier and Synergy in the past but as a workflow, visually manipulating multiple computers like this sucks. Few people need to do it and life is better if you can avoid needing to do it at all. Multiplatform development is the greatest win but still, the more you can minimise on-target testing, the better. A fast test harness on your dev machine is much nicer.
IMHO remoting into a machine is much less hassle than having a dedicated screen. Most use cases typically involve poking it now and again and having an occasional window on your main display is nicer than giving up desk space and properly aligning another display. If it's not part of your permanent setup then this extra display is often an ergonomic pest. You may be able to share peripherals but if you have to contort your neck to see it then ugh, it's not fun. It can be ergonomically nicer to use their own dedicated peripherals on a side table rather than sharing them.
If it's about sharing data then obviously network accessible storage (cloud, NAS or mount a remote machine's drive) is better.
See, that's the thing. My guess is you had to configure Synergy, and as a techie you're blind to this effort. But it is still effort, hence a time sink and a cognitive burden. The Apple version is none of these and a joy to use because Apple puts the emphasis on making it Just Work with zero configuration if possible.
Hundreds of millions more people will experience multi-device control for the first time with Apple Universal Control, than will have ever heard of Synergy.