Leave it to the British to shoot themselves in the foot for no reason. Why not Schuko / Europlug? Because we have to have our own standard that's worse, that's why.
Also not sure what you mean by "exactly the same". You can get single/double/triple in a variety of designs and colours. It's a socket - how much variation do you need?
"A variety of designs and colors" I only see a very few actually available, even via the internet (when I've looked). But you're probably right. I lived in the U.S. for a while, where variety in receptacles is easily obtainable.
Probably because the Brits had electrical appliances before the continent did.
Ring circuits generally way higher in power - and a lot more than a single appliance needs or could handle. Hence the need for a fused plug.
The upside is each socket can take a 13A plug (circa 3kW), whereas a standard US socket maxes out closer to 1.8kW.
https://en.wikipedia.org/wiki/File:SCHUKO-Patent.svg
Rather, I think the British decided to iterate (for better and for worse) on their earlier design that looks a lot like BS 1363.
Personally, having lived for an extensive amount of time in places with Schuko ("Europe"), NEMA ("US"), and BS 1363 ("British") plugs/sockets, I will take Schuko any day over the other two. Schuko stays in place, is grounded when it needs to be, is flexible when it comes to how it leads the cord out of the plug/socket, and so on. For all the touting of safety, "no sparks", etc. that we hear about BS 1363, I have never seen it out of a Schuko (NEMAs on the other hand...). Yes, BS 1363 improves upon NEMA, but that is a very low bar.