Few things to note..
IN most of Europe..people will not keep a carp, any carp if they are professional anglers. Some countries eat them of course..but for the angling community it is catch and release only.
Many carp caught are in man made lakes, this one is probably one of the same. Fishing in England, and especially France is much different then you guys view it here. Many carp waters are man made, with the largest being in France with carp being caught to 96 pounds now.
It is most likely 30 pounds. The reason it looks large is because of the photo angles and the holding of the fish. These anglers are extremely practiced in holding and posing, trust me. I like how they say "After an impromptu photoshoot"...Look at the guy, yeah that isn't a practiced pose, that's off the cuff...suuuure.
As for why it is so calm..it took 10 minutes to reel in. From personal experience with carp fishing and fish to 35 pounds..patience is key to the fight. Once netted most carp are tired and put up little resistance on the mat.
As for the color and shine..chances are it is fed, most carp waters are. Particularly on high protien boilies and/or pellets. Which also accounts for the round belly. Most wild carp are longer and more slender. A 30 pound river carp for instance might be slim and muscular where a 30 pound lake fed carp would be shorter but round. This is due to not having to travel miles daily for food. This is backed up by the " He spent 6 years trying to catch the fish." Which means it was in the same place for 6 years, at least. Meaning it was in a private, fed and stocked lake.
That said it doesn't mean it isn't an impressive catch..but I always like how the media plays with our heads