Yes, WSL2 is type-1 hypervisor (which means Linux under WSL2 and windows are both VMs of sort, managed by higher level invisible "main" OS) and initially this made running VMs inside windows impossible (since technically that would be VM inside VM). But this has been fixed for months now - originally not only it was not possible to run virtualbox (or vmware, ESXi is vmware type-1 btw, dont mistake it with free vbox) but also it was not possible to run docker either.
Edit: btw. this is why it took so long for WSL2 to be released to public; they gave time to most of the VM solutions to adapt to the fact windows would be running under type-1 hypervisor.
The virtualbox VM launches but it is too slow to be usable, kind of like a car that only goes 5 mph. So slow in fact that virtualbox shows the little turtle icon on the status bar.
Yes, WSL2 is type-1 hypervisor (which means Linux under WSL2 and windows are both VMs of sort, managed by higher level invisible "main" OS) and initially this made running VMs inside windows impossible (since technically that would be VM inside VM). But this has been fixed for months now - originally not only it was not possible to run virtualbox (or vmware, ESXi is vmware type-1 btw, dont mistake it with free vbox) but also it was not possible to run docker either.
Edit: btw. this is why it took so long for WSL2 to be released to public; they gave time to most of the VM solutions to adapt to the fact windows would be running under type-1 hypervisor.