Although I definitely agree with your post, and part of the desirability of single family definitely stems from space for outdoor activity, I don’t think that’s the main reason for most people. It’s more because SFH is what people are used to. Everyone they know lives in SFH, they’ve lived in SFH for decades, etc. Many people frown upon living in any other type of housing at all.
Certainly that plays a role. But that's also a reality with which we must contend. If people imagine they need more living space indoors or out, then that's what they'll demand be built, at least for a period of time. Changing that is the art of a gentle push and pull; and also finding ways to create a better in-between model, as it were.
Obviously these are just some general statements, and there are definitely people who make good use of the outdoor space. However, there are also a decent number of people who don’t use the yard at all, and another significant number that only occasionally use very small parts of the yard.
I think the balcony size that I indicated as being full-service, would meet most people's needs for a back yard (22 x 8); with a larger family, perhaps a bit more, assuming a tree in the back yard, I would want the tree to get 15 x 15 on its own to allow it grow to full maturity; but even with that, assuming a 22' wide lot, a back yard of 22 x 24 would be ample. Many people do have considerably more; and most don't need it, even from their own perspective.
Also, wrt sense of community, I’d say “isn’t great” is a bit of an understatement
. Honestly, it’s practically nonexistent imo. I pretty much never talked to any neighbours living in an SFH. Maybe that’s just me, but the sense of community definitely is not a good reason to live in an SFH.
This is why I used the word illusion.
In my experience, there is a high sense of community in a small number of SFH communities; that's typically about a few extroverted and caring souls, not the built form.
It is, less common in tower-form; but not entirely absent; and as I noted, I think some modest design change can both boost the illusion; and create a bit more encouragement where the right people (said extroverts) are present.
Also, as a random aside, I think building homes in a block with a communal backyard and no front yards would be a good idea. You don’t want too many units sharing the yard in order to foster a better sense of community, but it would be much larger than a fully private backyard (more useful), but also can waste less space and cost less to maintain per household. Expensive and infrequently used items like pools can be more easily funded and better utilized. The front yard can be ditched to put buildings right up to the street in order to create a more human scaled street and eliminate the fairly useless front yard.
On the couryard configuration, the blog/post linked above speaks to some of the challenges; but in general, I'm not opposed. In fact, I think its more durable than the poster/blogger thinks, but that's a different post!
However, I would add one caveat; while I agree front yards aren't that useful to most people.........
The one thing I genuinely dislike about European streetscapes is their lack of trees, and it does have serious environmental consequences. Now, trees don't need to be in a 'yard'; but you do have to think, assuming you want them; about where they would go in front of homes (does every sidewalk get a wide boulevard or greenway?; how are you addressing stormwater running off the roofs of nearby buildings? Ideally it would have a chance to penetrate the ground and absorb, in most cases one small back yard would be insufficient/impractical. There are other options......a wide enough greenway, supported by infiltration piping would work well.
The other thing we would have to discuss is how create an animated, quality ground floor on non-retail streets.
It can certainly be done; but Europe is not all 'Disney land' in this respect; it has its share of fails.
A ground-floor residential unit with no veranda/porch/patio etc is unlikey to animate the street.
The old Euro-blocks sometimes achieve that by way of large, openable windows, often with pretty window boxes full of flowers; people open those windows and can literally call to a neighbour across the way from their window to the next.
In a street wide enough to support even a single row of trees this becomes less viable.
But there are greater challenges.
Those openable windows work, because they lack screens that we require here.
They work because air conditioning isn't common, so you open your windows during the day and both sides of the house to get a cross breeze.
They work because its not so cold you wouldn't open your windows but for a couple of months each year.
Translate that to a new-build in Toronto.
It will have screens, it will have air conditioning, the winter makes opening large windows undesirable for 5 months of the year.
This is not to suggest we ought not to try this built-form, only that its difficult to cleanly recreate.
We also aren't going to go car-less overnight; and a built form that relies on far fewer cars is not one we can instantly replicate. Hiding said cars underground also has impacts on the growing conditions above, stormwater drainage, streets which support access to/from said garages, and those have real cost implications as well.
