And that did happen, we don't have a single decent affordable personal computing ecosystem at this point. The only good personal computing ecosystem is with Apple, which makes its money by selling proprietary software mostly but is not affordable to ordinary joe.
What an ordinary person can buy, is an ad-riddled machine like a windows desktop or a chromebook, where although the software is not proprietary, they're basically selling you ads(directly or indirectly through your data).
To tie it back in, in fact open source software did rise up and proprietary software did go down, but we lost the pure software aspect that came with proprietary software. Basically, open source software is being used to sell you ads and if the ads based business goes down/stops so does open source ecosystem.
If you haven't realized, the biggest parts of the open source economy are propped by FAANG and Microsoft. If these big whales go away, open source's vibrancy will vanish in a poof.
In fact open source software creation is hugely concentrated to North America and by extension FAANG. So if FAANG were to stop sponsoring open source, we'll be back to proprietary software age soon. So, I'm not convinced of your argument that "open source" has won conclusively.