Either Collison or his brother or both have been funding an abundance-y think tank in Ireland which has been the subject of some public controversy (complaints about "red tape", etc.) Their genius proposal for increasing housing supply and density was to let homeowners build sheds in their back gardens and rent them out to people, a proposal our unscrupulous right-wing coalition government took on despite, you know, all the drawbacks of creating a new source of poor quality housing with insecure tenancy. I don't have it in me to go looking up facts about those two gobdaws at this hour but there has been reporting by the Dublin Inquirer on the think tank.

Edit:

With think tank Progress Ireland the yimby movement here is powering up

(I can't go in and pick out quotes cause I'm over my free article limit but trust me there is some stuff in there to make your monocle pop out)

"Government plans to allow homeowners to let modular ‘garden homes’ on the private rental market have been described as “scraping the bottom of the barrel” in terms of finding a solution to the housing crisis."