Which desktop are you running where you can't figure out how to take a screenshot? Maybe some of the more tech-savvy folks here at HN can help you figure it out.
Since you edited your post I'll rephrase my question: Which desktop are you running where you can't figure out how to share your screen? Maybe some of the more tech-savvy folks here at HN can help you figure it out.
The fact you're griping about implementation details like pipewire makes me think you also tried micromanaging your env and broke something. If you use a fresh install and leave everything default, I'm sure it would work for you like it does for everyone else. I use KDE too btw.
All the "micromanaging" you need to do to not have screensharing is one of the following;
1. Don't have a started dbus session
2. Don't have portals installed and setup
3. Don't have pipewire installed and setup
Meanwhile on X what you need is:
1. Have X
So no, it wouldn't work, the reason why it works for those people in the Reddit post is because they use distros and sessions that do all the things I listed that make screensharing not work if any one is not done.
PS: Wayland does have testing protocols for screenshots and screenrecording like 'wlr-screencopy' and some DMA buff one I forgot the name of. But for screen sharing there's nothing that Wayland implements itself afaik.