Can you imagine a place that uses imperial units next to metric units, in some unholy alliance that’s clearly worse than imperial units alone? Welcome to the UK, bruv.
Meanwhile the standard metric measure is 500ml. So US would benefit from dropping the pint in favour of metric, while UK drinkers would be understandably reluctant. Unfortunately, most UK bottles are now 500ml, thanks to shrinkflation. Newcastle Brown held out for a while, so did ciders, but these days pint bottles are quite rare.
Even better, we refer to bottles of liquor as a pint, a fifth and a handle. A pint is 375ml, a fifth is 750ml and a handle is 1.75l. Not even mixed - metric volumes with US customary names.