I think part of it is that it is a complex ecosystem to understand. What is qemu, what is KVM, what is virt-manager, how does it all fit together. It is actually not hard to use but it is confusing to understand at first, what is used for what etc.
Either you are into it, and you know, or the need to create a VM has just arose and you want to quickly do it. In the later case from my Fedora 31 system I search for "Vir"(tual), it tells me about "Boxes", I open it... and it can't be simpler. I end up with a Virtual machine with QEmu/KVM without ever having to know what QEmu/KVM is, as far as random user knows "yesterday I had problems with VirtualBox kernel modules, so I created a VM with Boxes".
