Can someone from Steinberg please explain this image to me? 
And no, it’s not due to ASIO drivers or latency. The CPU usage in task manager is the real CPU usage. 
CPU performance and VST performance are not the same.
CPU performance measures the actual strain on the CPU, VST performance relates to CPU performance, but it also depends on the ASIO drivers, the buffer size, the system configuration, etc.
The user chimpspanner posted a video which explains this pretty well:
Best,
Thanks for wasting 30 mins of my life on a beginner video. Perhaps I wasn’t being clear; I don’t have issues with my PC or real-time performance. My issue is with Cubase average load being way over what the actual CPU load is. This issue started since I switched to windows 10, and cubase is the only DAW which has this issue on win10.
Perhaps this image will show it more clearly:
Look at the average CPU usage cubase is displaying! Then check the actual CPU usage. My real-time meter is nowhere near max and is not causing the issue. The same project on win7 shows the right amount of CPU usage, which is a lot less, around 55%.
This was explained already: they are not the same thing. The VST Performance meter is not a CPU meter.
Looking at the difference between real-time and average load, I would guess ASIO Guard is enabled. As a rough indication, when AG is disabled and the system reacts as expected, the RT and avg. meters should be hovering around similar values (at lower latencies, the RT will always be higher, at higher latencies and with AG enabled the RT meter might even show no activity at all).
Those are two different OSs, they will need different configuration. A good place to start would be to update the motherboard drivers, but it looks like the last updates for yours date back to Win 7 (assuming the system you are using with 10 is the one in the signature): http://www.gigabyte.de/products/product-page.aspx?pid=3449#dl
If no updates for that motherboard are planned, your best bet is to set the power options (high performance), tweak the BIOS to have all throttling disabled (Turbo Boost, C-States, EIST) and test if HT on or off make any difference for you.