4K HDR
Normally I use kdenlive to edit video, which supports 4K AFAIK, but although that doesn’t support HDR it looks like DaVinci Resolve supports both.
Taxes
That’s surprising. Turbotax and Quickbooks have online options, and there are a few native apps like GnuCash, but I haven’t used them—TurboTax works for me.
GarageBand
Yeah that’s too bad. I hear good things about Ardour, though. Also, bandlab if you’re okay with a webapp.
Netflix
I only stream on an actual TV, not my computer, so I haven’t done this in a while, but I thought you could do this in Firefox with DRM enabled? If not, seems like there are addons which enable it. Might be outdated knowledge.
vector illustration
Fun is hard to come by
git client
Git clients all suck for me, CLI is the way to go. However, my co-workers that use git clients all use GitKraken (on macOS) and that is available on Linux, too.
screen recording was also painful
Won’t argue with you there. Don’t know why it doesn’t have first-class support in many distros. I hear OBS Studio works well for this if you want to do anything fancy with the recording, otherwise there are plenty of apps for this (Kazam might be a simpler choice).
barely meets my use cases
I think really (considering the above) your main issue is that you just have some strong software preferences. There are certainly ways to meet most if not all of the use cases you listed. It requires a big change in workflow, though.
For what it’s worth, I find that most of the issues with software alternatives in Linux is that everyone often recommends free/GPL replacements, which are invariably worse than the commercial/non-free software the user is used to. But there is paid software in Linux land, too, remember. In my case, I have often found that if I can pay for the software it will be better, and if there’s a webapp version of something non-free it will often be better than the native FOSS alternative. There are many notable exceptions to that rule, but money does solve the occasional headache.
That is absolutely fascinating. I had the same assumption.