Apart from actual system administration or kernel developing, there’s no real “learn Linux” .
Video/Photo/Vector editing on Linux is not “learning Linux”, it’s learning to use a tool which runs on Linux. You can learn to use Blender, Gimp or Inkscape on Windows. You don’t edit videos/photos/vectors with the Linux kernel. You can even “learn the linux terminal” installing bash on Windows.
You can also install Visual Code or IDLE on Windows and on Linux. Learning to code on Visual Code or IDLE is not really “learning Linux”.
Also going on distro hopping looking for the “perfect distro” many times means the hopper simply doesn’t stick to one long enough to learn how to customize the environment to their liking (which usually means the window manager).
Most of the things you can do on the GUI, even the administration ones are just layers and layers of tools to make things “easier” - and they’ll be different on each distro and release. Command line administration will change much less, or at least less frequently.
Things I consider “learning Linux” are for example:
installing Linux (specially a headless server)
understanding how to use the package managers - again, on the command line
understand how systemd works
(hard core) dive into the kernel workings
understand how grub works
learn the general filesystem structure
learn how to analyze logs
learn user administration and how the permissions (and extended permissions) work
learn how to integrate Linux to a Windows environment (join a workgroup or domain, share storage, authenticate users)
learn how to check resources usage and how to troubleshoot it
understand the nuances and of partitioning and when they are needed, as well as the different filesystems
etc (and /etc)
And yes, many of those are not strictly “Linux”, but are specific to a Linux system, unlike photo editing.