I think you're generalising your experience a bit here. I have zero issues sharing the clipboard between macOS, Fedora, and Android using KDE Connect. It runs quietly in the background, and all I had to do was tweak a couple of settings and forget about it. For my use cases and device topology, it works pretty much like Apple’s Universal Clipboard. And this is coming from someone deeply familiar with what the Apple ecosystem has to offer.

That said, I do believe you're having a bad experience with your particular combination of devices, and I fully understand that for your use cases the Apple ecosystem may be a better fit. At the end of the day, you use tech to get work done. You don't need to feel embarrassed about it. I'm not trying to diminish your status as a "power user" or push OSS. You are well aware of the trade-offs. Just saying that if you're not yet 100% convinced to abandon your Linux setup and sell your ThinkPad, you can still try to either tinker or throw money at the problem. Not dismissing your very valid frustrations with KDE Connection, nor telling you what you should do, just giving you two options besides rolling back and selling your ThinkPad 🤣