It would be cool to customize the nav bar; change or adjust:
background color
transparency
font-color
size of nav bar
vertical/horizontal layout
which buttons are visible
default position of navbar (on Youtube shorts, the VideoSpeed nav is blocked by the YT play button)
leave nav bar expanded
add navbar to videospeed toolbar icon, see image; for backup where in-video toolbar may be blocked (YT shorts)

Current color palette of nav bar is so understated, it's almost invisible.
My preferred layout would be just: decrease speed and increase speed. I would turn off the rewind and advance buttons.