Of course, they also spent about 25% of their income on food (seasonal and mostly local; mostly vegetarian with small meat portions) compared to 6% today.
I'd be curious when the changes in diet started in terms of eating more meat.
Anyways, there's still expenses people didn't have to worry about back then. Typically the wife stayed at home (almost always) which is part of the reason why incomes were lower, but it also meant you didn't have to worry about childcare expenses and probably a few other things.
You also didn't have to spend as much on university education since an average job today requires a post-secondary education vs just a high school degree back then. Although much of that cost is state subsidized, that's still a cost (via taxes), and it's also less time a person spends on education while they still need housing, food, etc provided for them and time not spent earning money. Healthcare costs are also higher (mostly via taxes).
Also while cars were less expensive back then, you didn't really need them while today 95%+ of Canadians live in a place where they're at a serious disadvantage if they don't own a car. I'm not sure how infrastructure costs would compare, we do have more roads, highways, etc per capita.
The low interest rates of today do help make housing more affordable, but I think it's risky to assume they'll stay that way for the next 25 years.
I also don't know what the writer of the article used for the definition of a home with "civilized conveniences and modern facilities" in Detroit. That city certainly had very much of an "out with the old, in with the new" mentality at the time.