

Yeah I’d second that. It’s good for discovering valid settings as you get start, and then once you want to do more complicated stuff, the XML option view becomes useful, and then if you want to try on CLI after all you can start using virsh to administer the same VMs.
At least that’s how I progressed through the stages as I started messing with a Windows VM for a game that doesn’t lend itself to hosting on Linux natively.
The size difference is not significant. This is about the maintenance burden. When you need to change some of the code where CPU architecture specific things happen you always have to consider what to do with the code path or the compiler flags that concern 486 CPUs.
Here is the announcement by the maintainer Ingo Molnar where he lists some of the things he can now remove and stop worrying about: https://lore.kernel.org/lkml/20250425084216.3913608-1-mingo@kernel.org/