It's a huge lump, but it handles 240 v at 13 amp and does so without burning down houses or killing people who plug it in.

I have no idea how many sockets are installed in UK houses and how many plugs are fitted to UK equipment but a new plug / socket design would have to be God-Tier to justify the cost of replacement.

Also, I've seen people wiring plugs and it's sometimes scary, so anything that avoids the need for many people to botch a new plug onto their equipment is a good thing. And I guess this is where most improvement has happened - plugs that can be built quickly, cheaply and safely in Chinese factories for use in UK. You can change the fuse, but the plug is molded and you can't take it apart.