I live in one of those communist era flats in Eastern Europe. There is four of us and we live in a two bedroom flat, around 82 square metres. Most of our friends live in flats like ours, although there are some who live in one bedroom apartments and parents sleep in the sitting room, and children have bedroom.
I have never been in a british home, but I have seen hundreds of property show set in UK (how real are they for a typical british family, I do not know).
From what I have seen there are lot of differences that make our life easier, even though we live in small flats.
Hallways are bigger where I live, everybody has a wardrobe for shoes in hallway, so we do not keep shoes in our rooms. I have three huge custom made closets in my hallway, they keep lot of storage.
Our kitchens are small (participants of Escape to the country would run a mile if they had to cook breakfast in my kitchen), but most of them have 1 m2 pantry behind the closed doors.
We have several huge parks one minute walk from my apartment building and kids usually play there. It's summer now and it is wonderful to see all parents and kids playing and talking after 6 pm. Because of hot weather, most of the kids are in the park till 9 pm, even 10 pm, when it is cooler. I guess it is our garden.
Our bathrooms are built with washers in mind, so every builder leaves a place for a washer, so they do not have to be in kitchen. People also usually have one bin for dirty clothes and it always in the bathroom. And out bathrooms are small, usually three square meters.