I think they mean that ARM became dominant by widely licencing its RISC architecture to pretty much anyone. This startup wants to make RISC V designs and licence them to various chip manufacturers - so they won’t be in the business of making chips themselves, just the design.

But as long as they are RISC V chips, then they would run the same software as any other RISC V chips.

Would that be a risk? Isn’t the whole point of RISC V that its ISA is open and free to use? That’s not the case for ARM or Intel’s x86 architecture.