Speaking as an older gen-Z-er living in with their parents, this is very true of me and many people I know around my age (most, now that I think about it). If I could live somewhere nearby that doesn't eat up 50%+ of my income I would go there in a heartbeat. On HN there's a tendency to assume people are either well-off or destitute drug addicts who have given up on life but there's a wide range in between.
In general I don't think many homeless people are going straight from the street to their own market rate unit. However some of them might be able to move into a sibling's spare bedroom after their adult nephew moves out.