There's been a longstanding issue open regarding the Carbon website and the vertical alignment of text with certain components, carbon-design-system/carbon#3922

After some further debugging, it appears the cause is the usage of the variable font. When I flip between the variable and the non-variable font family, a noticable shift happens. So far I've seen this in iOS Safari, Chrome, and Firefox. In the videos below I override the font family to be non-vf, wait for the build to finish which automatically updates the browser after a few seconds - you can see the text shift at the end of each video.