It seems to me this accounting is missing the significant financial contribution many companies make to open source by way of paying employees to contribute, either part time or full time.
Many of the arguments here are premised on the idea that the only valid model for open source funding is a donation model. But if a company believes they get more benefit by contributing via employment instead of patronage, I don’t think it’s fair to say they’re exploiting open source.
(Disclaimer: I work at a BigCo where my role sometimes involves open source and standards bodies)