RISC-V is probably no different than ARM at it's core. Also, both of them are RISC ISAs.
Right now, you are far more likely to use RISC-V and not know it than to knowingly interact with RISC-V directly. For example, since about 2015, Nvidia has used RISC-V as an onboard controller for their GPUs.
Western Digital also announced they were looking (have already?) to move to RISC-V.
If you manufacture items at scale, getting away from ARM licensing costs per unit makes financial sense. Especially if you already have in-house expertise who can design chips tuned to your specific requirements.
Right now, you are far more likely to use RISC-V and not know it than to knowingly interact with RISC-V directly. For example, since about 2015, Nvidia has used RISC-V as an onboard controller for their GPUs.