Chrome back/forward gestures reversed on Big Sur
That sounds like the right direction. The previous page is semantically to the left of the current page, so swiping right with natural direction is going left. This is the same as swiping PDF pages in Preview — swipe right to go to the previous page on the left.
This description of natural scrolling in the macOS User Guide:

Scroll direction: Natural
Select this option to move the contents of a
window in the same direction as your fingers.

and the animation in System Preferences &gt; Trackpad &gt; Swipe between pages:

make this logic hopefully clear.