Thanks! I checked through those searching for an answer the question of "How much of 'all' software is FOSS or depends on FOSS?", but I could only find one study, not a range of studies - Synopsys - whose full report requires email registration (and it's not a peer-reviewed research paper): https://www.synopsys.com/blogs/software-security/open-source-trends-ossra-report.html