We've had many types of cottage industries in US (probably elsewhere, too).
I don't think such biz-models had started with the Blockbusters of the DVD era, or tattoo shops, or bookstores...
But there is one 'cottage' industry that will never disappear, as long as people live in houses.
I am guessing that there are more "plumbing" businesses than any other type of independent "skilled" cottage industry.
I wanted to see if this observation can be backed-up with numbers of plumbers in comparison to not just house repair specialists (i.e.garage door fixers, fenestration peeps, etc.) but then, I remembered that I can't readily access the Yellow pages anymore either.
I live in terror about water-leaks as a home-owner and I cannot be the only one.
I am in the hope that the huge numbers of plumbers will be kept in check, when enough home-owners start incorporating Water Leak Sensors/Detectors (IoT?) all around their houses.
Such devices can be had for dirt cheap and certainly should be added to our "water damage insurance" stash like the sump-pumps, etc.
No! I am not practicing what I am preaching here... yet!