Anyone who want a simple Virtual Machine and have to go thought cumbersome installation procedures like this one just to reach the end and have error messages saying virtualization isn’t enable when, in fact, it is… or trying to use GNOME Boxes and have a sub-par virtualization experience.

MS Office I get, it's not replacable for power users. Virtualization though? That's one of Linux's strengths. Your issue lies with trying to use VirtualBox, by far one of the worst virtualization solutions (both on Windows and Linux). Linux has QEMU and LXC, two of the most mature virtualization/containerization technologies, use them. If you need a UI for it you can use virt-manager (or "Virtual Machine Manager"), it uses QEMU as backend.

As for GNOME Boxes, everything in the GNOME ecosystem is made to be trivially easy. As such it lacks essential features for power users. In general, if you need avanced features, KDE might be better for you.

Even finding a decent and working FTP/SFTP/FTPS desktop client (similar WinSCP or Cyberduck) is an impossible task as there a few, but they all fail even at basic stuff like dragging and dropping a file.

As @Zamundaaa@discuss.tchncs.de mentioned, both Dolphin and Nautilus have integrated SFTP/FTP support, you literally just type sftp://host.example.org into your title bar and you are there. It will even use your existing SSH keys out of the box.

If you need a dedicated UI, you can also use FileZilla. It's included in most repos and I haven't really found anything it can't do that WinSCP can. However, I would really recommend looking into how to do this via Dolphin/Nautilus. There's no level of integration any application can achieve that works as well as being integrated directly into the file browser. If Nautilus is too simple for you (it was for me), Dolphin works on GNOME as well.

I think a lot of your issues stem from being used to do something on Windows and trying to reproduce the same workflow on Linux. That will sometimes work but some workflows have simply developed differently on Linux and if you don't try to accomodate them you will just bang your head against the wall for nothing. If you find there's a lack of development for tools on Linux, the most likely reason is simply because nobody is doing it like that.

Linux desktop is not perfect but it's in a very good state nowadays and quickly improving with every update. It's in a state that makes it better for my use cases than Windows, which is going backwards with every version.