There is a massive wealth gap between the older generations (Silent and Boomers) and the Millennials and to a lesser extent, Gen-Xers.
What it means is that in terms of purchasing power, people over 55 have over 70% of all the wealth (while this article is about the US, I imagine that most western countries follow similar patterns). Yet, most marketing, according to our friend Bob Hoffman spends an inordinate amount of money trying to woo Millennials, who have practically none of their own. Oh, the irony.
This is an opportunity for residential architects. Since most of the people with money are over 55, they could kill two birds with one stone by marketing to older folks offering beautiful residential architecture that is sustainable (thus catering to the desire to leave a legacy), well built (leaving properties to their children after they're gone) and accessible (allowing them to age in place with dignity). Some have tried exactly that with great success, but alas few, if anyone, have followed in their footsteps.
Yet, the overwhelming majority of architects cater to... no one. They position themselves as generalists who can do it all. I truly believe that the architect who will explore that niche shall see riches beyond what most others can only dream of. A friend of mine who is a GC routinely suggests his clients shore up their basement in order to have a first floor that's at-grade and thus accessible, which in turn allows for an additional floor above. The combination of extra square footage up top and a basement with high ceilings, more than makes up for the extra construction cost by increasing property values by a multiple of the additional construction costs.
Pair that with prefabrication and the replicability of design and only the sky is the limit.