

They’re referring (I believe) to the screenshot right at the top of the article, which includes this absurd calculation:
border-radius: max (0px, min(8px, calc( (100vw - 4px - 100%) * 9999)) );
My guess (hope!) is that this is not ‘serious’ code, but padding for the sake of a screenshot to demonstrate that it’s possible to use each of these different features (not that you should!).
But then for that you have distrobox, which is great. If that’s not enough, running another OS is also trivial, so that downside really is only ‘kinda’, as you say!