These arguments fall apart when the animal is anthropomorphized.
Dogs sleep a lot more than people do, needing around 12 hours. They will take about 4 hours of that sleep in the day regardless if a human is around.
It's very breed dependent but, the majority of dogs don't require a significant amount of mental stimulation. For most breeds, a half hour of mental stimulation is plenty.
Obviously locking a husky or a cattle dog in an apartment (and this unfortunately does happen), is another story. There are certain breeds you shouldn't go for if you live in an apartment. But there are a lot of breeds that do just fine, even some large ones, like greyhounds.
Speaking of greyhounds, we fostered an Italian Greyhound one time...and I thought Frenchies were fragile.
Now that we both work from home we can see that the dog mostly sleeps all day, occasionally getting up to bark at some squirrels or passers-by.
And it might be affection they give their dogs but it's not really love if they are so cruel. Besides, they wouldn't be strays if they were never bought, at least not a lot of them if the demand were lower, then so would the breeding and supply.