I experienced something similar back when Microsoft decided to usurp all hypervisors made for Windows and make Windows itself run as a VM on Hyper-V running as a Type 1 hypervisor on the hardware. That made it so other VMs could only run on Hyper-V alongside Windows or with nested virtualization.
So this meant VMWare, VirtualBox, etc as they were would no longer work on Windows. Microsoft required all of them to switch to using Hyper-V libs behind the scenes to launch Hyper-V VMs and then present them as their own (while hiding them from the Hyper-V UI).
VirtualBox was slow, hot garbage on its own before this happened, but now it's even worse. They didn't optimize their Hyper-V integration as well as VMWare (eventually) did. VMWare is still worse off than it was though since it has to inherit all of Hyper-V's problems behind the scenes.
So this meant VMWare, VirtualBox, etc as they were would no longer work on Windows. Microsoft required all of them to switch to using Hyper-V libs behind the scenes to launch Hyper-V VMs and then present them as their own (while hiding them from the Hyper-V UI).
VirtualBox was slow, hot garbage on its own before this happened, but now it's even worse. They didn't optimize their Hyper-V integration as well as VMWare (eventually) did. VMWare is still worse off than it was though since it has to inherit all of Hyper-V's problems behind the scenes.
Hope this brings some clarity.