boye vs susan bates

can someone please explain to me why both of these hooks are "G", and although they're different brands, they're also TOTALLY different!!

the boye brand "g" hook is 4.25mm. the susan bates brand "g" hook is 4.00mm. and it may not seem like THAT big of a difference...

but look how different the hooks actually are!!

i learned the hard way the difference 0.25mm can make!

and when you google crochet hook sizes, some say a G should be 4mm. and that's from the craft yarn council! (who knew such a council even exsisted, lol)

and others say it should be 4.25mm.

SO WHO'S RIGHT?!?! and why is this the only hook that has this issue?