On the subject of measures, rather than Brexit, we have a real mish mash in the UK now.
If asked, most people would give their height and weight in imperial measures. Unless they have much contact with medical people, then it’s metric.
Looking at restaurant menus portion sizes, of grills for example, are usually given in ounces.
Go to a DIY store and just about all timber and sheet materials are metric.
Buy a burger and it’s a quarter pounder very often.
I buy my milk in pints, but my spirits in litres.
I buy my fuel in litres but measure consumption in MPG.
The attempt to force standardisation upon us has caused lots of confusion and resistance from the general public.