You don't need paravirtualization to do dynamic memory allocation -- all VMs do this.
No. Gen1 images use a fixed allocation pool instead of an oversubscription model. You need a gen2 image with a cooperative memory allocator on the guest in order for this to work properly.
Well, so barring ancient HyperV versions, all VMs do it. This is more of a guest thing than hypervisor thing, anyway. All the VM needs to support is balloning and this is completely unrelated to paravirtualization.
The link you posted only contains one device and it happens to be an ARM device. Seeing the impact it still has on battery life at least on x86, I really doubt they have enabled it by default. It was not enabled by default on x86 in 2020 at least.
That's just a blog post about the feature being deployed, of course it won't have many examples. Take any PC from the past few years and install Windows 10 x64 on it. It will have VBS enabled and hypervisors that do not support Windows Hypervisor Platform won't work. That's been my experience since at least 2017. If you click through "capable hardware" to here[1], you'll see the list of requirements for VBS, includin…
Well, I'm asking because my experience is exactly the opposite. I've installed Windows countless times on systems with all the requirements and HyperV is not enabled. The day it starts being enabled, I don't even want to imagine the number of support calls.
The link you posted only contains one device and it happens to be an ARM device. Seeing the impact it still has on battery life at least on x86, I really doubt they have enabled it by default. It was not enabled by default on x86 in 2020 at least.
Do you have a reference to the increased power consumption that running a hypervisor causes? This thread is the first I've heard about it, and I would like to learn more.
No, and I also would like to find some academical test. Try it -- you can even dual boot hypervisor on/off. It's not a small effect. Around 1h extra one on "almost idle" scenarios.