Any industry needs competition! Sadly the consolidation of the [server] processor market over the last decade from half a dozen or more very different designs (which had collectively driven computing for the last 30+ years) has left us with the duopoly of Intel who's not really innovating and ARM who kind of are, but mostly in mobile.

Obviously, RISC-V also needs software support; gcc supports it, Golang has added RISC-V as a target (although it's not yet implemented) and there are several projects working on LLVM (e.g. lowRISC and SiFive's port). Having played around with the Fedora-RISCV port under QEMU, it's actually surprisingly good thus far.

Having an open-source processor design with good software support that anyone can manufacture without royalties is a good thing and will hopefully spur both Intel and ARM into innovation.

Removal of "percentage of revenue" based royalties is probably the big one. Others may cite the open source ISA, but I think royalties is the big deal. See Western Digital's plans for RISCV. Taking a 1.5 to 2 percent "off the top revenue/not-profit skim" away is a big deal.

Edit: Fwiw, I hope the open source ISA has secondary societal benefits. I'm not skeptical, just pragmatic. Follow the money.

Neither AMD nor Intel offer x86 chips that give end users full access to the highest privilege levels.