Look at the plugs and sockets in the rest of the world: those fused UK plugs are really prehistoric and needlessly oversized. Whenever I show them to students they can’t stop laughing.
They've a very different job to do, compared with how even 240Vac supplies are wired in homes elsewhere, since they have to address the ability of the UK's post-war shortage-driven 'ring' main' solution to deliver a
bsolutely massive fault currents into any fault in the in-room 'flex' cable the plug supplies any downstream in -room eqpt.
That
can be dealt with by other methods today: but in the day of fuses, a very different thing. So tehre's a useful legacy, which is:
The thought behind the way the BS1362 plug is designed; the way in snagging the flex cable cannot accidentally dislodge the plug, the absolute -only - fit-one-way need to avoid polarisation issues; the attention to avoiding touch-shock risk if one isn't inserted correctly, the oversized pin conductors that have a terrific effective wiped surface area ( to deal with huge max prospective fault current, never approached); the strain -relief on the in-room flex cable; the way that the Earth Bond is the
first connection made when plugging-in (and only when engaged in place,
then-unshutters the active conductors ); and the fact it is so utterly bloody, tediously reliable - makes the rest of us look at most equiv systems and think 'wtf/" too …
Esp. since few equivalent worldwide plugs are in any way usefully smaller (why might smaller be a measure of improvement , btw? you call it 'oversized' ) - but are demonstrably more fragile in all above respects of safety & integrity - yet not as easy to wire DIY! Schuko is not a valid answer
Oh yes - that's another thing: the way the BS1362 plug is designed,
also means if the flex strain relief fails / was incorrectly set - not that many other plugs worldwide even have one - the flex cable Earth bond is the
last to come free: it has a deliberately longer route/labyrinth to ensure this.