This is a discussion thread. No real decision has been made yet. We are still looking into what will be the best option.
That doesn't change the way the Linux-Kernel has been built. The Kernel already includes the necessary driver side support for Intel-CPUs.
What you linked to there at askubuntu isn't a driver. It's microcode. Microcode is something completley different and again, only applies to your HOST, not Whonix or any other non-host-system. It is a sort of firmware, not a driver. Furthermore, it is, as already mentioned, off-topic.
Microcode is not necessary to run Linux, it just includes minor fixes from the maker of your CPU, though again, only for HOST-SYSTEMS, nothing virtualized, including nested-virtualization.
Adding to all of that, even if this were drivers AND they would have any purpose in Whonix, we wouldn't have the right to include those out of the same reason no Linux ever includes proprietary GPU drivers. Because it wouldn't be legal.
Though since non of this has anything to do with Whonix, that doesn't matter anyways.
tldr; Has nothing to do with Whonix, isn't a driver, and only applies on host.
Have a nice day,