How an SVG document is displayed always depends on the SVG viewer application used. (That is simply how SVG works.) Out of five SVG viewer applications that I tested, three (yEd, Chrome, Firefox) displayed your sample SVG document one way and two (Emacs, Inkscape) displayed the document another way. Hazarding a wild guess, I think the fact that the left-hand-side SVG document uses millimeter units and declares an explicit viewbox while the right-hand-side SVG document uses user space units and declares no viewbox leads to problems. Unfortunately, I know way too little SVG to decide which viewer is right. (Actually, I think even an SVG expert would be hard pressed to decide which visualization is correct due to the many transformations used inside your original SVG documents.)
See also SVG export bug? some custom symbols change their size when export is opened in Inkscape.