The dominant machine languages—the language compilers compile programs to so that the code can run on the silicon—are all proprietary and protected by patents. RISC-V offers a free, open-source machine language, as well as open designs for the hardware. You can more or less download their designs for free and send them off to a factory to make high-quality processors.
Intel and AMD have put backdoors in their CPUs - Intel with the Management Engine and AMD with the Platform Security Processor.
These are separate sub-CPUs required by both platforms to boot and run. Both of these CPUs run proprietary, encrypted, otherwise-inaccessible and inauditable code that is always running and has full access to everything the CPU has access to.
The Intel ME in particular is part of Intel's offerings that allow remote access to a system even if the operating system fails--it's accessible remotely by design, and flaws have already been found in it. Only Intel can update the ME. Only Intel knows what's in the ME and what it's doing, same for AMD and the PSP.
I think people want RISC-V to succeed because it gives privacy-conscious individuals a chance to have a truly secure platform not 100% under control of a single company with 100% auditable code from each stage of the boot process.
It's also a much more efficient processor architecture.
On paper it's same as x86 or ARM but RISC-V is modular and open that means that ever manufacturer can extend it and modify it for specific cases. That means more efficient niche devices like small computers, tablets, robots and all sorts of cool stuff and all of them running on same architecture!
The fact that we're stuck with this blob for processor architecture is just sounds so archaic when you learn about RISC-V.
However, as soon as you start modifying/extending hardware you take on enormous risk and require considerable more expertise and development time. Yes, a modular design may allow you to disable your extension (if it's bugged) and still get a saleable device but then you've spent all those extra resources for no benefit. Not to mention the huge quantities you still need to make this financially viable. Basically, it'll cost you a load more to do something custom, you could have just used the next model up for less. RISC-V can't solve any of this.
I guess you could argue that you can build your more efficient hardware with an older, cheaper process and maybe still end up with something competitive.
I don't see the tablet market being served by RISC-V, what benefits does it bring?
Someone like WD getting onboard makes some sense but that's not exciting, they just want to save a bit of cash.
RISC-V is an open ISA (Instruction Set Architechture). An ISA is the "language" that the silicon speaks and which eventually all the programs are "compiled" into. Being an open ISA means anyone can implement a chip based on it for free. To this day, most ISAs are either locked-down or available under a license + royalty scheme. That means, you have to either buy a chip off the shelf from a vendor (either physically or a design you include in yours) for a cost or you have to design one yourself.
Again, being open means anyone can design one, and several free (as in beers) designs have popped up already. Anyone that needs a CPU in their system can pick one of these designs and use it "for free". Moreover, a company can design one such chips, and then outsource to another company the support for it (or the other way around). Or, even swap support companies if needed. The fact that the RISC-V is open (and claimed to be patent free) means there is very little barried to entry. Which means the market offers space to more companies working together and competing at the same time.
For lots of designs, the CPU is a commodity. You need it, but the specs are not that important in the sense that you do not need the performance equivalent of the latest Intel chip. For those markets, haven a proven design with lots of software support and that is gratis, is way more appealing. Another commenter pointer rightly so to the "hidden" CPUs that are everywhere inside devices and gadgets. That's the market that I believe RISC-V is going to conquer quickly because the "cost" of moving to another architecture is low compared to other segments where it is very expensive. Think of a PC or smartphone which carry years and years of software developed all over the world and built against a specific ISA. Those markets are unlikely to move soon, if ever. However, the "hidden" CPU ones is easy, the washing machine software is built inside the wasching machine company which can probably built their software against a different ISA in a couple of days, if needed.
Another important aspect is the software tools. It is cosly both in time and in money to develop a high quality set of tools to support an specific ISA, i.e. compilers, support libraries and optimized libraries for your ISA, etc. Therefore, not all architectures receive the same "love". Some "niche" markets do, with lots of effort in the closed source space, which again means vendor lock-in. RISC-V, being open, is getting lots of attention from all open source tools, and it's expected its support will be on par with other mainstream architectures like x86_64 or ARM ones.
One final note is that of developers and knowledge. The fact that is free and anyone can experiment with it, means lots of universities are turning their focus on it for reasearch and education. As the new wave of engineers come out of the university with expertise in RISC-V, it's going to be easier to hire them and their friction-less path is going to be towards RISC-V.
