You cannot buy the company backing RISC-V to take out the competition. And if a RISC-V company stumbles, the ecosystem carries on. But if even one RISC-V company is in the right place at the right time, RISC-V can surge ahead. It is hard to imagine it does not dominate eventually.
But I also think this is an example of a slight disingenuity in RISC-V being referred to as open-source. It's borrowing the clout of open-source software projects where the end user has the freedom to compile them at home. I can't fabricate a CPU at home, I'm still beholden to whatever patents the manufacturer chooses to license. SiFive have a >billion dollar valuation, for a business based on selling licences.
Nowadays nobody will want to work on foundational open source work for free only to enrich everyone else that builds on top of it.
You get these kinds of responses when something is too close to perfection. It suddenly gets judged in a much different light.