You're on the right track. But imho it's about hitting a sweet spot in whatever the market wants @ a certain time. There's a lot of luck involved. x86 hit that

You're on the right track. But imho it's about hitting a sweet spot in whatever the market wants @ a certain time. There's a lot of luck involved. x86 hit that sweet spot: 8088/8086 performance nicely between much-weaker, memory constrained 8-bitters and too-expensive SPARK/MIPS/Alpha etc workstations. Then the BIOS situation opening the door for PC clone builders, Intel's good fabbing, and presto: x86 took off. People just bought PCs because economies of scale provided increasing bang/buck compared to other offerings. ARM: grew steadily in embedded. Then "mobile" became big, ARM was objectively better than x86 there (battery! perf/W), and the market size provided huge $$ royalties that enabled ARM to hire top-talent engineers & improve their next designs. Leaving their competition in the dust. Steadily upping performance lead to things like ARM based laptops & servers. RISC-V is largely riding the "open" wave. Which does translate into practical advantages like driving down product cost, software support improving fast due to the shared ecosystem, etc. But again: much luck involved - timing of its introduction, cheap FPGA boards becoming available to developers & students, the ISA itself being fairly sane (even called "boring", which is good in this context), its modularity positioning it across a wide range of markets, coumtries like China looking for tech-independence, etc. This much like ~1850's industrialisation in Britain: ANY one of the factors missing could have lead to failure. Personally I have high expectations for RISC-V. But regardless how it'll pan out: it's well past critical mass, so it's here to stay.