Not everyone wants a yard and/or a dog! Very, very, few people modify their houses in ways that wouldn’t be applicable to apartments/flats too - interior changes are common, but exterior is usually far too much money for far too little in return. And if you’re complaining about people calling them “apartments”, which is what they’ve always been called in the US, I assume you’re in the UK where terraced houses are the most common form of housing, and neighbours are on both sides anyway. (Is it possible you’re hearing people calling flats apartments because of the influence of American TV? Where are you getting “fancy” from, or assuming it’s just because the same word is used in French? Do you avoid American TV shows? They were extremely common on British TV when I was growing up. If you’re not in Britain, apologies! But it seems likely, given most other English speaking countries I can think of use the term too.)
I personally disagree with anyone who promotes a one-size-fit-all approach to housing etc, but I don’t actually think most advocates of density really are doing that. They’re usually Americans fighting the completely insane zoning laws and building practices in the US that force people to own cars, make public transport uneconomic except with massive subsidies, and require Americans own houses that are far bigger and more expensive to maintain than they need. Nobody’s actually better off because of these laws, not even the people who want to live outside of real cities and drive to work - it ends up taking just as long to get to the supermarket to get a gallon of milk in a suburb where you have to leave your home, get into your car, drive it, drive out of your residential neighbourhood where businesses like supermarkets are banned, drive it past large numbers of buildings built for individual businesses each with enough parking to support the maximum number of customers it might conceivably need, 5-10 minutes later getting to the supermarket’s parking lot, which is again, absurdly oversized because it has to have one parking spot per potential customer, finding a spot, walking across this vast expanse to the supermarket, and then doing the same thing in reverse. Time savings? Nil. Tesco was five minutes walk away when I lived in the UK, and while that was unusual, most places I’ve lived in the UK had some kind of supermarket within walking distance. Money savings? Worse: my grocery bill tripled when I came to the US and I had to pay gas prices and for car maintenance on top of that. Not surprising when every store needs 4X as much land as it needs in the UK, just so it has enough parking.
So that’s what the pictures are likely about. The option of high density housing ought to be available to everyone, in the UK it is for the most part, hence it looks odd to you and you’re assuming the intent is to take your detached or semi-detached house from you. But in the US, no it isn’t, the few places that have good high density development are either impractical to live in, because you still need cars to work, or uneconomic for most people because those places are in such high demand to live the property prices are astronomical (think SF or NYC.)