To my understanding, vacant housing refers to housing in which someone is not currently living, including housing that is under repair/renovation, needs repairs, or is abandoned/condemned.
https://darrellowens.substack.com/p/census-reveals-vacant-housing-mysteries
Also, of the housing that is vacant, two thirds are vacant for 6 or fewer months, and ~85% are vacant for 12 or fewer months. The median duration of vacancy is about 2.4 months. Only a small portion of vacant housing is actually vacant in the way people typically think when they hear vacant housing. Freeing up the ~10% of housing that is actually vacant long-term the way people think just would not alleviate the housing crisis. We gotta build more housing, y’all.
https://www.tiktok.com/@divasunglasses/video/7189814160165702955
It’s not altruistic, but the blog post outlines why they’re doing this. Underappreciated volunteer-run dependencies can have security flaws that impact huge swaths of the tech sector. Investing a few grand now to secure those tools instead of significantly more money to do damage control after a vulnerability is found and exploited makes sense. It’s a preventative measure that benefits the entire industry, GitHub and its parent company Microsoft included.