1. There's no big ecosystem of compiled ARM code to prevent people moving to RISC-V. In the embedded world everything is always compiled from source so it doesn't matter. On Android everything except games is bytecode. Maybe on Windows/Mac... but that's probably the last place we'll see RISC-V.

2. ARM and RISC-V are much more similar than ARM and x86 so it is way easier to translate ARM to RISC-V. It's also much more extensible so you can easily add instructions that you need to make the translation easy. I believe ARM has some instructions that are specifically included to make running x86 code easier - that sort of thing would be even easier on RISC-V.

You're probably right about price being the major differentiator, but I wouldn't underestimate that! Especially with ARM turning the screws on license fees.