I think if you gave KDE a try, you'd be really surprised. I too like fancy screenshots with drop-shadow compositor effects and transparent elements; the Spectacle screenshot utility does this perfectly for me, and can be bound to a universal keybind. Desktop utilities like 'peek' give you instant gif-recording capabilities for the more advanced stuff, and of course there are full-fledged apps like OBS for more advanced capture work.
> That said, I would be more than happy to pay a substantial annual license fee for a Linux experience that rivals that of MacOS.
Are you looking for BSD?
Joking aside, you're going to have to be a lot more specific than "rivals" MacOS. There are a lot of cases where MacOS has dug itself into arbitrary, insurmountable leads (eg. nobody is going to add haptics to your touchpad with a software update), but there are also cases where Linux whoops MacOS up and down the block (full WINE functionality, Vulkan drivers, Nvidia compatibility, system-agnostic filesystems, etc.)
> A lot of this functionality simply does not exist on Linux. With multi monitor setups, virtual desktops scroll on both screens. Gnome 4 is the first DE to pseudoreplicate MacOS's model.
This is tacitly untrue, KDE scrolls all monitors by default, and most x11 sessions can be configured to do the same afaik. The only holdouts are esoteric window managers like i3wm, where arbitrary desktop/monitor association is just part of their design paradigm. I'm pretty sure GNOME 3 could be configured to do the same, too (the developers just didn't put the option in the default settings app because they don't trust you, I guess). Not sure where you're getting this impression from, but it sounds like a misunderstanding.
> Screenshots and screen recordings are close but lack the nuance of MacOS (and Windows) that make them valuable. For instance no DE offers the ability to draw notes on a screenshotted area, copy the modified version to clipboard (rather than save a file).
Again, KDE's default screenshot utility ("Spectacle") has robust annotation and saving options. I just let it save the screenshotted areas to my clipboard, and it works fine. It should probably be compatible with your GNOME system too, if you want to try it out.
TL-DR:
Linux is not MacOS, for better and for worse. Most of the features you've listed are indeed configuration options, but nobody really ships a "MacOS clone" distro because it doesn't exist. You can't pay developers to make something like that because there's not a single other organization on earth with 200 billion dollars in liquid cash to spend on decadent UIs and eye candy.